Lesson I: INTRODUCTION

Basic Computer Tutorial

This basic computer tutorial is written for those who do not know very much aboutcomputers. The purpose of this basic computer tutorial is to help the reader betterunderstand how to use their computer more effectively and safely. It will help the readerunderstand:

What files and file types areHow to copy filesWhere your files are storedWhat the parts of your computer areWhat an operating system isWhat a computer program is

Security and Performance

With the above basic information, this tutorial will explain methods that you can do tomake your system more secure, keep your data safe by backing it up, and avoid mostperformance degredation caused to bad applications and SPAM.

How some file types can be used by third parties to gain control of your computerHow to modify your file view settings so you are not as easily fooled by e-mailscontaining virusesHow to prevent viruses and wormsHow to reduce SPAMHow to back up your filesHow to reduce or eliminate unwanted programs that could reduce your systemperformanceWhat to do if you receive a virus or wormWhat to do if you receive an e-mail telling you that an e-mail you sent contained avirus

This basic computer tutorial gives some basic information about hardware, operatingsystems, and programs in the first half to help the reader understand later informationabout files, e-mail and computer security practices. Depending on the reader’s level ofknowledge, some of the basic information may be skipped and the reader may refer tothe terms page if they do not understand some of the terms.

PHASE I: COMPUTER HARDWARE

Lesson II: COMPUTER DATA

To help understand computers it is best to first learn about computer data. Computerdata is information required by the computer to be able to operate. It is used to:

Run programs – this is the actual executable program data that the computer willexecute to run the program such as Microsoft Word.Store program or system configuration information.Store information that the computer user needs such as text files or other files thatare associated with the program the computer user is running. A common exampleof a program the computer user is running is the Microsoft Office suite of productswhich include Microsoft Word, Microsoft Excel, and others. These programs are alsoknown as applications.

Data Structure

Computer data is in what is called binary format. This means that it is always a 0 or a 1.It only has these two states and must be in one of them.

There are several fundamental data units which include:

Bit – a data unit which must be in one of the two binary states described above. Itis the smallest data unit that exists.Byte – 8 bits of data which has a possible value from 0 to 255.Word – two bytes or 16 bits of data with a possible unsigned value from 0 to16535.

Data Transmission

Data transmission is the act of sending data from one place to another. Data istransmitted both inside and outside your computer. There are two fundamental methodsof data transmission.

Serial – data is sent on a single line and one bit is sent at a time. This is similar to aline which one item must come one after another.Parallel – data is sent on more than one line at a time. This may be any number ofbits at a time, but is usually one word at a time (two bytes) or possibly three bytesat a time.

Lesson III: COMPUTER HARDWARE

The term computer hardware refers to the various electronic components that arerequired for you to use a computer along with the hardware components inside thecomputer case. As you know your computer equipment is made of several commoncomponents. These include:

The main computer boxA monitor-looks like a television screenA keyboardA mouseSpeakersAn optional printer

The main computer box is the main component of the computer. It has computerhardware parts inside that perform the following functions:

Temporary storage of information (known as data in more technical terms) – thisfunction is done by memory.Permanent storage of information – this function is done by a hard disk, floppydisk, or CD ROM.Manipulation or processing data – used to determine where data is stored andperform calculations which support operations that the user is doing.Interfacing to the outside components or to the outside world – this supports theability for the user to communicate with the computer and know how the computeris responding to commands which are done primarily through the monitor,keyboard, and mouse along with their interface components in the main computerbox.A power supply which provides the electrical power to the components in thecomputer box.

The Main Computer Box

The main computer box is made of several computer hardware components andsubcomponents which include:

The case - The outside component which provides protection for the parts insideand provides a fan and power supply which is used to both cool the working partsinside and provide power to them.

The motherboard - Hold the following computer hardware subcomponents:

Memory - Used to provide temporary storage of information as discussedearlier.

Microprocessor - Used to provide the processing of data function asdiscussed earlier.

Video interface card which is also called the video card - This card is aninterface between the computer monitor and the motherboard and itssubcomponents such as the microprocessor and memory. This card may be

included as part of the motherboard or it may plug into a card slot on themotherboard.

Sound card is an interface between the computer speakers and themotherboard and its subcomponents such as the microprocessor andmemory. This card may be included as part of the motherboard or it mayplug into a card slot on the motherboard.

One or more permanent storage devices some of which may be optional:

Hard disk - Most computers today have a hard disk (sometimes called harddrives) which is the component most commonly used to provide permanentstorage of data. Hard disks are usually permanently installed in a computer.

CD ROM drive or DVD drive - Used to provide permanent storage of data butthis type of drive is used to bring information into the computer morecommonly than it is used to store information from the computer. Sometimesthis type of drive is used to back up data from the hard drive so data is notlost if a hard drive breaks. A DVD drive holds more data than a CD ROM driveand DVDs have enough storage capacity that they may be used to play orstore movies. The storage media, the CD ROM or DVD may be removed fromthe computer.

Floppy Drive - A low capacity storage device which can be written to as easilyas it is read. The floppy disk may be easily removed from the computer. It iscalled a floppy because the part of the media that holds the data is on amaterial that is not rigid but it is enclosed in a more rigid case to give itdurability.

There are also other minor computer hardware components inside the case which includecables which may be used to hook other internal parts together along with connecting aninterface to the case for printers and other devices such as a high speed serial bus calledUSB. (A serial bus simply refers to the fact that data is sent in a stream which is likesending one bit at a time.

The Case

The drawing below shows a typical case. It may help you understand where yourconnections for your monitor, keyboard, mouse, and other devices are if you should needto hook them up. For more specific information you should refer to your computer owner'smanual.

The drawing below shows a typical layout of the components inside your computer case.

Lesson IV: HARDWARE & SOFTWARE

Hardware

The term hardware describes the physical parts of your computer which you canphysically touch or see such as your monitor, case, disk drives, microprocessor and otherphysical parts.

SOFTWARE

The term software describes the programs that run on your system. This includes yourcomputer operating system and other computer programs which run. Software is writtenin a computer language (such as Basic, C, Java, or others) by programmers. Thecomputer language is in text format and can be read by a person although if you do notunderstand the structure and rules of the language you may not understand it very well.Once a program is written, an operation is performed on it which is called compiling.Compiling is the process of changing the textual written language into a binary languagewhich can be understood by the computer.

Writing these text files and converting them to computer readable files is the wayoperating system and most application programs are created.

BIOS (Basic Input/Output System)

BIOS is normally written in a low level computer language and are permanently orsemi-permanently written into the computer system. This type of computer program iscommonly referred to as firmware since it was historically written permanently intocomputer systems. Although BIOS is a program, because of its permanent state, it wasnot quite considered to be software so the term firmware is used to describe it.

Historically BIOS programs were written into a type of memory called ROM (read onlymemory). This type of memory would not lose its data when the computer lost power thusensuring these BIOS programs would always be available. There were different variants ofROM memory some of which could be written multiple times but this memory could notnormally be changed or re-programmed once the computer system was sold to thecustomer. Once ROM memory was written to, it could not be written to again and couldonly be read when in the possession of the customer. In more recent years a more flexibleform of memory was developed called flash ROM which allows ROM memory to be writtento after the computer system is in possession of the customer.

Lesson V: WHAT IS A NETWORK?

The word network can be used to describe a very large and complicated set of equipment.In its most accurate and simplest definition a network refers to the cables and electroniccomponents that amplify the signals going through the cables. The amplifying equipmentis necessary to ensure communication and make the signal stronger if it needs to go longdistances.

Broader Definition

When many people talk about a network, they are talking about a network using a verybroad concept. For instance if someone cannot get to their email, they may say “thenetwork is down”. Likewise they may say this if they cannot surf the internet or get totheir files. They may not stop to think that in each specific instance there is a single pieceof equipment that may provide the capability which they are trying to use.

Most people who work on a corporate or organizational network think about the networkin component parts. The three main parts are:

The cabling and amplifiers mentioned in the first paragraph.

The workstations which most members of the organization to access resources.

Higher powered computers called servers – these are the machines that providewhat network administrators call services. Services include the functions that mostpeople try to use such as email, reading and writing files, printing, and getting tothe internet. Whenever a user is trying to do something on the network, there is aservice or machine providing the capability to do so. This even includes times whensomeone is trying to get to network resources from their home.

Services

Services include:

Email service

File service – allows users to use and share file space on a computer with a lot offile space.

Print service – allows printing to printers connected on the network.

Web surfing – allowing someone to open web pages and see web sites on theinternet.

Filtering out undesired on the internet.

Allowing someone to access the network from the outside (from home).

Updating virus definitions on workstations.

Allowing someone to log onto the network.

Even giving a workstation an address on the network is a service. If your computerdoes not have an address, it cannot access the internet or any other resources onthe network.

A Typical Network

A typical corporate or organizational network is shown below:

Of course there are variations on this network layout and some details have been left outfor the sake of simplicity but this drawing should give you some idea about what goes onbehind the scene on the network at your organization. Some servers and server functionshave not been shown here.

The firewall is the device that protects all computers in the network from many attacks. Itallows some types of network traffic into the network from the outside, but usually onlyfor mail or web services. Usually the internet traffic that that is allowed to come into thenetwork is routed to the part of the network labeled "DMZ" on the right side of thediagram. DMZ stands for demilitarized zone and is also called a semi-private network. Inthis DMZ is a web server which is used to allow people surfing on the internet to see webpages posted by the organization. A mail server is also shown in the DMZ but this couldbe replaced by a mail relay server while the mail server is placed inside the privatenetwork. The mail relay server would forward mail traffic from the outside to the mailserver. This would increase the security of the network since a direct connection from theinternet to the mail server would not be allowed.

The private network is of course the most secure part of the network. There are severalservers on this network including:

A login server (called a domain controller) which controls everyone permissions andaccess to the network resources such as files. Without this server, they cannot loginto the network.

An address server (called a DHCP server) which provides addresses to computerson the network so they can communicate as discussed earlier.

A file server which provides common files and a private folder for users.

A remote access server which allows users to connect to the network by telephonefrom the outside.

Also the workstations are part of this network.

Conclusion

Knowing the above information, if someone cannot get their mail, they may think thenetwork is down. This is not likely to be the case. The mail server may be down but thenetwork is not likely to be down. The same goes for when someone can't surf the web.There may be a problem with the firewall or the line connecting to the internet, but it isunlikely that the whole network is down. When problems are noticed it is best for the userto describe what they were trying to do and what happened.

Lesson VI: WHAT IS INTERNET?

The word internet is used to describe a network of networks which incorporate a verylarge and complicated set of equipment. To understand the internet, there are three areasof discussion which are very helpful. These include the various services provided acrossthe internet, the functions that enable the internet to work, and the various organizationsthat are part of the internet.

Internet Services

The main services used on the internet include:

Web browsing – supported by the HTTP protocol, this function allows users to viewweb pages using a web browser.

E-mail – allows people to send and receive electronic messages.

Other lesser used services includes telnet (allows remote login to computer), FTP (allowsquick file transmission to remote computers), and gopher (an early form of text basedform o reading internet documents which is rarely used today).

Internet Functions

The internet provides for the following two functions which support communications.Without the communications support mentioned below, the internet could not function.These two functions are provided by internet service providers listed below under the“Internet Organizations” header/

Physical lines that data is sent across.

Routing of data – there are special machines on the internet called routers, thatdetermined where data needs to go to get from the sender of the data to thereceiver of the data.

Internet Organizations

ISPs (Internet Service Providers) – they provide the connection to the internet forusers and also provide routers that direct internet traffic.

Corporations or Web hosting providers with mail servers and web servers – theyprovide the information posted on the internet and virtual data connections to othermail servers.

There are also other organizations that regulate the internet, providing communicationstandards and designing new communication standards for improvements. Thesecommunication standards are also known as protocols.

Summary

So the internet is a collection of organizations that provide equipment that support theinternet functions and services. The internet connects many corporate and organizationalprivate networks together thus enabling all these organizations to easily communicate.

Accessing the Internet

People use an internet browser to access web pages that are available across the internet.Internet browsers include Microsoft Internet Explorer, Netscape Navigator, Mozilla, andothers.

Web pages are created in a marked up form of text file called HTML (Hyper-Text MarkupLanguage). The markup within the text indicates documents structure showing whereparagraphs begin and end, what items are in a list, headers, tables, and other documentstructure.

When people are browsing of surfing the internet, they usually go from place to place byclicking on links. These links are locations for specific pages and indicate the three thing:

1. Protocol being used such as http or ftp

2. The domain that the web page is found on. This will point to a specificorganization’s or company’s web server.

3. The location of the page on the server including the directory path and file name.

An example link is "http://www.comptechdoc.org/basics/bastutorial/osintro.html". In thiscase http is the protocol being used, the comptechdoc.org domain indicates where theorganization's web server is, and the "/basics/bastutorial/osintro.html" part of the stringindicates the folders the file is in and the name of the file.

These links are sometimes called hyperlinks or URLs (Uniform Resource Locators)

PHASE II: OPERATING SYSTEM

Lesson VII: Operating System

What is an Operating System?

The operating system is the core software component of your computer. It performsmany functions and is, in very basic term, and interface between your computer and theoutside world. In the section about hardware, a computer is described as consisting ofseveral component parts including your monitor, keyboard, mouse, and other parts. Theoperating system provides an interface to these parts using what is referred to as“drivers”. This is why sometimes when you install a new printer or other piece ofhardware, your system will ask you to install more software called a driver.

What does a driver do?

A driver is a specially written program which understands the operation of the device itinterfaces to, such as printer, video card sound card or CD ROM drive. It translatescommands from the operating system or user into commands understood by thecomponent computer part it interfaces with. It also translates responses from thecomponent computer part back to responses that can be understood by the operatingsystem, application program, or user. The below diagram gives a graphical depiction ofthe interfaces between the operating system and the computer component.

Other Operating System Functions

The operating system provides for several other functions including:

System tools (programs) used to monitor computer performance, debug problemsor maintain parts of the system.

A set of libraries or functions which programs may use to perform specific tasksespecially relating to interfacing with computer system components.

The operating system makes these interfacing functions along with its other functionsoperate smoothly and these functions are mostly transparent to the user.

Operating System Concerns

As mentioned previously, an operating system is a computer program. Operating systemsare written by human programmers who make mistakes. Therefore there can be errors inthe code even though there may be some testing before the product is released. Somecompanies have better software quality control and testing than others so you may noticevarying levels of quality from operating system to operating system. Errors in operatingsystems cause three main types of problems.

System crashes and instabilities – these can happen due to the software bugtypically in the operating system, although computer programs being run on theoperating system can make the system more unstable or may even crash thesystem themselves. This varies depending on the type of operating system. Asystem crash is the act of a system freezing and becoming unresponsive whichwould cause the user to need to reboot.

Security flaws – some software errors leave a door open for the system to bebroken into by unauthorized intruders. As these flaws are discovered, unauthorizedintruders may try to use these to gain illegal access to your system. Patching theseflaws often will help keep your computer system secure. How this is done will beexplained later.

Sometimes errors in the operating system will cause the computer not to workcorrectly with some peripheral devices such as printers.

Operating System Types

There are many types of operating systems. The most common is the Microsoft suite ofoperating systems. They include from most recent to the oldest:

Windows XP Professional Edition – A version by many businesses on workstations.It has the ability to become a member of a corporate domain.

Windows XP Home Edition – A lower cost version of Windows XP which is for homeuse only and should not be used at a business.

Windows 2000 – A better version of the Windows NT operating system which workswell both at home and as a workstation at a business. It includes technologies

which allow hardware to be automatically detected and other enhancements overWindows NT.

Windows ME – A upgraded version from windows 98 but it has been historicallyplagued with programming errors which may be frustrating for home users.

Windows 98 – This was produced in two main versions. The first Windows 98version was plagued with programming errors but the Windows 98Second Editionwhich came out later was much better with many errors resolved.

Windows NT – A version of Windows made specifically for business offering bettercontrol over workstation capabilities to help network administrators.

Windows 95 – The first version of Wi8ndows after the older Windows 3.x versionsoffering a better interface and better library functions for programs.

There are other worthwhile types of operating systems not made by Microsoft. Thegreatest problem with these operating systems lies in the fact that not as manyapplication programs are written for them. However if you can get the type of applicationprograms you are looking for, one of the systems listed below may be a good choice.

Unix – A system that has been around for many years and it is very stable. Itprimary used to be a server rather than a workstation and should not be used byanyone who does not understand the system. It can be difficult to learn. Unix mustnormally run an a computer made by they same company that produces thesoftware.

Linux – Linux is similar to Unix in operation but it is free. It also should not be usedby anyone who does not understand the system and can be difficult to learn.

Apple MacIntosh – Most recent versions are based on Unix but it has a goodgraphical interface so it is both stable [does not crash often or have as manysoftware problems as other systems may have] and easy to learn. One drawback tothis system is that it can only be run on Apple produced hardware.

Phase III: APPLICATIONS

Lesson VIII: Application Programs

What is an application?

Applications are programs that are installed on computers to give users the ability to dospecific task. For example, Microsoft Word® is a programs that gives the user the abilityto write documents. Some program packages come in a set with multiple programsincluded to provide multiple capabilities such as the Microsoft Office® suite of programs.The suite of programs also includes Microsoft Outlook® which is used to send and receivee-mail. It also includes other programs with more capabilities.

How Application Programs Work

Application programs are written in a text based computer language as mentioned in thesection about hardware and software. Once written, they are compiled into binary

language the computer understands. The application programs use function calls [asdescribed in the section about operating systems] to interface to the various computerperipherals such as your keyboard, mouse, screen, printers, and other devices. Most ofthese function calls are provided the operating system such as Microsoft Windows 2000®,Microsoft Windows XP®, or Microsoft Windows 98®.

Application Problems

An application program is a computer program. It is written by human programmers whomake mistakes. There for there can be errors in the code even though there may be sometesting before the product is released. Application programs vary widely in the quality ofthe code. Errors in code are referred to as “bugs”. Bugs can cause unpredictable resultsincluding system crashes, inability to perform expected functions, or providing an exploitfor an attacker who wants to gain control of your system.

Application Acquisition and Installation

You get applications several ways. The most common way is to purchase it in a store andyou will brind a CD home and install it on your computer system. The ways you may getapplications include:

Purchase of a program from a store.Download a purchased program on the internet.Down load a shareware program on the internet.Download a free program on the internet.

Whether purchasing a program or downloading one for free on the internet, you should beaware of the quality of the product you are placing on your computer system. Ask yourselfthe following:

Do I know who made this product and are they a trustworthy source?If the product is free, do I know why it is free?Is there some hidden purpose for the product?What is the reputation of the marker of the product?What problems do users of the product have?

Before downloading a product or purchasing a product you should always spend at least afew minutes researching it. You should at least do a quick search on the Gigablast searchengine using the product and the name of the product producer. You should perform aGigablast internet search and possibly Google groups search to find out where discussionsabout the product have taken place. There are also many product evaluation sites thatcan be used to obtain reviewers and users ratings of the product before you buy or installit can also cause your privacy to be invaded.

Bad Applications

There are many types of application that can cause problems on your computer system.

Applications with serious bugs.Applications that come with unwanted programs. Some applications come withadditional software that may not really want but is installed by default. Normally

this is only annoying and may slightly slow your system down when its bootsbecause some of these items will load every time you start your computer.Adware – Most adware comes with programs that may be purchased ordownloaded for free on the internet. Adware will cause advertising popups toappear an your computer. Besides being annoying, they will slow your ability toaccess the internet. Many times these programs will download other ad programs.These programs are very difficult to remove from your system because they areusually hidden on your system very well. Many times it requires an expert toremove these programs but later I will give you some tips on how you can eitherremove them or render them effective, but to be able to do this you must havereasonable knowledge about your system. There are some programs written toremove adware programs which I will discuss later.Spyware – This usually comes with some free programs and it will monitor yourinternet activity and send information to some corporation. This type of program isnot normally seriously harmful but most people do not want to have there activitiesmonitored. There are also programs to remove Spyware but it is best to not installit in the first place.

If you do your research before installing applications you will avoid most problemapplications. It is best to ask your IT support personnel about an application before youinstall it. In fact many corporate IT policies are set to users cannot install programs oncorporate systems can joepardize computer security for entire organization.

Application Files

Applications have a variety of files they use for basic purposes.Executable filesConfiguration filesData files used by the user such as Microsoft Word® document files.

PHASE 1V: FILES

Lesson IX: What Files Are?

Files are collection of data onto a permanent storage structure. They are stored on apermanent storage media such as a computer hard drive, CD ROM drive, floppy disk driveor sometimes even a tape drive. Files take a certain amount of room to store. Forexample you have two text files and one file has one sentence in it while the other file has200 sentences in it, the file with 200 sentences will use more room on the storage media.

File Functions

Different files have different purposes. Files are used to do one or more of the followingfunctions:

Provide machine executable code which is used to run application programs and dooperating system.Store application program o operating system configuration information.Store data used by the user such as Microsoft Word document files.

Therefore there are three types of information that files contain:

Executable code.System of program configuration information.User data.

These files are read by an application program or the operating system.

File Characteristics

Files have the below characteristics:

NameOptional extension name – Part of the name, it is used by Windows operatingsystems to identify an associated programs that can be used to read it.Size – Shows the space the file requires for storage normally showed in kilobytes[Kb] which is 1000 bytes.Type – Indicates the program used to access the file. The next section will talkmore about file types.Date Modified – Shows the last date the file was created or changed.File structure – This characteristics is not viewable by the computer user but someprograms can examine file structure to determine the type of file it is even whenthe file extension is changed.

The mean items to remember include the facts that all files take a certain amount of roomon their storage media and all files have a type which indicates whether they can be runby your computer. The file extension in one indication of the file type but not the only wayto determine type.

If you are browsing your files using “My Computer” an click on “View” and “Details” youwill see a window showing the file characteristics like the one below. Folders only take alittle room on the hard drive and do not normally take as much room as files.

Lesson X: File Types

Because file can have different purposes, they have different types. The file type is bestidentified by its file structure. For example a text file would have a very different structurethan a file than can be executed. An executable file must have a specific structure to beable to be run. The file structure is used to determined its MIME type. The word MIMEstands for multipurpose internet mail extension and is used as a standard to identifyvarious file types.

File Extensions

In operating systems such as Microsoft Windows systems, Linux, and Unix, a fileextension is used to help identify the type of file. On Microsoft Windows system, many filetypes are associated with a particular program which can read the file. For example a filewith a pdf extension can be read by the Adobe Acrobat application program.

Files are actually identified by what is called a MIME type. This can be done because filesthat are executable have a different structure than a data structure. Therefore fileextension are not the only way to identify a file type nor are they the most accurate.Apple MacIntosh computer system do not use a file extension to identify file types.

Executable File Types

The most important file type to be aware of are executable file types. This because if youaccidentally run an executable file on your system, it may install a virus or some otherunwanted software program. Executable file types include:

.com

.exe

Lesson XI: How to Manage Files

File Management

File Organization

Files can be placed in folders similar to the way single sheets of paper can be placed intofolders in a file cabinet. Folders can be created on the hard drive or nested inside eachother any way the computer user desires.

Browsing Your files using Windows

If using a Windows operating system double click on the “My Computer” icon on yourdesktop. A window like the one shown below will open.

The first drive in the window shown is floppy drive. It is labeled as drive A. the seconddisk is the system hard drive labeled as drive C. The third disk shown is a data disk shownas drive D. This is not a normal setup on most systems but I like to use a hard drive to

hold my data that is different than the hard drive that holds the operating system. DrivesE and F are compact disk [CD ROM drives] of which one is a read/write drive.

The dive letters will vary defending on how your system is configured and defending onwhether you have any network drives. If you do have network drives, you should usethem for the mail place you store your files on network drives are usually backed upnightly in most organizations. If your files are not backed up and your hard drive fails, youwill lose your data.

Copying Files

There are several ways Windows operating systems allow files to be copied or moved.They include:

Drag and drop – In the window above it is easy to drag one of the files into one ofthe folders. This will move the file into the folder. This can also be done by openingthe windows using the “My Computer” icon and dragging the file from one windowto another.Copy and paste – You can open a “My Computer” window, and do following:

● On the “My Computer” menu select “Edit”, then “Copy”.● Navigate to the location where you want to put the file. You can navigate by

using the “Up” folder to go up one level into the folder structure or by double

clicking on folders to enter them. If the “Up” folder does not exist in your “MyComputer” window, on your menu select “View”, then “toolbars”, then select“Standard Buttons”.

● On the “My Computer” menu select “Edit”, then “Paste”. The file will copied tothe location you have navigated to.

Copying Multiple Files

There are several tricks that can be used to make copying or moving multiple fileseasier. They involve the selection of the files to be copied or moved. You can hold downthe Shift key and select one file by clicking on it with the left mouse button [called leftclicking]. While still holding the Shift key down left click on another file several files downon the list. This will cause all files from the first one through the last one selected to behighlighted and selected. Release the Shift key. After this, you can hold down the Ctrlkey and by left clicking on any other files, they can be either selected or de-selected.Release the Ctrl key. Once you have selected the files you can move them by draggingand dropping them [after releasing both the shift and control keys] into another folder.This done as follows:

1 Put the mouse cursor over one of the selected files.2 Left clicking the muse and hold it down.3 Drag the file into the desired location such as a folder icon.4 Release the left mouse button.

If you want to copy the files:

1 On the “My Computer” menu select “Edit, then “Copy”.2 Navigate to the location where you want to put the file.3 On the “My Computer” menu select “Edit”, then “Paste”. The file will be copied to

the location you have navigated to.

Lesson XII: Windows File View Settings

View Settings

The Default Windows Setting is Dangerous

Windows systems come with default file view settings. The default is to “Hide fileextensions for known file types”. This setting can be used to deceive a computer user intobelieving that a file is safe to open when it is not. Files containing viruses can be sent to acomputer with a name “document txt exe” which is a file that the computer will run. Thefile will appear to the computer user as “document txt” making the user believe that it issafe to open, but if the user clicks on it the file will be run and be able to infect thecomputer.

Changing the View Settings

This section will tell you how to change your settings so you will always see fileextensions. It will also tell you how to beable to see file details.

Open “My Computer” by clicking on the “My Computer” icon on your desktop. Click on themenu item “View and select “Details” from the drop down menu. This will change thecurrent settings for the folder or location you are in, but the change is not permanent yet.

To change the file view settings, if you are using Windows 2000 or XP click on the menuitem “Tools” and “Folder options” selection. If you are using Windows 98, click on "View",and "Folder options". A dialog box similar to the one below should appear.

Click on the view tab and the dialog box will change as shown below:

Click on the button in the Folder Views area that says "Like current folder" and answer yeswhen asked if you want to change all folders to match the current folder. Change the restof the settings to match the dialog box as shown below:

The first three selections are display settings which make it more convenient to navigatethrough files and folders. Be sure and uncheck the checkbox next to "Hide file extensionsfor known file types". If you are using Windows 2000 or Windows XP, this should be donefor every user that logs in since each unique user that uses the machine will get their owndesktop and user profile.

Lesson XIII: File Backups

File backups are very important to protect your data. Is your hard drive fails or youroperating system malfunctions, you could loose all your data. If you do regular backups,you will drastically reduce the data loss that could occur.

Using the Network for Backups

Backing up your data is very important. If you are operating on a corporate ororganizational network and have disk drives shared from a file server it is likely that filesstored there are backed up every night. If possible you should store your files on thisserver.

Since Windows operating systems use the "My Documents" folder as the location to storeyour files by default it will be helpful to set up your system so the "My Documents" folderpoints to one of your network drives. If running a Windows 2000 or Windows XP system,you can right click on the "My Documents" folder ether on your desktop or displayed from

the Start menu and select properties. A dialog box similar to the one shown below willappear.

File backups are very important to protect your data. Is your hard drive fails or youroperating system malfunctions, you could loose all your data. If you do regular backups,you will drastically reduce the data loss that could occur.

Using the Network for Backups

Backing up your data is very important. If you are operating on a corporate ororganizational network and have disk drives shared from a file server it is likely that filesstored there are backed up every night. If possible you should store your files on thisserver.

Since Windows operating systems use the "My Documents" folder as the location to storeyour files by default it will be helpful to set up your system so the "My Documents" folderpoints to one of your network drives. If running a Windows 2000 or Windows XP system,you can right click on the "My Documents" folder ether on your desktop or displayed fromthe Start menu and select properties. A dialog box similar to the one shown below willappear.

File backups are very important to protect your data. Is your hard drive fails or youroperating system malfunctions, you could loose all your data. If you do regular backups,you will drastically reduce the data loss that could occur.

Using the Network for Backups

Backing up your data is very important. If you are operating on a corporate ororganizational network and have disk drives shared from a file server it is likely that filesstored there are backed up every night. If possible you should store your files on thisserver.

Since Windows operating systems use the "My Documents" folder as the location to storeyour files by default it will be helpful to set up your system so the "My Documents" folderpoints to one of your network drives. If running a Windows 2000 or Windows XP system,you can right click on the "My Documents" folder ether on your desktop or displayed fromthe Start menu and select properties. A dialog box similar to the one shown below willappear.

Click on the "Move" button. A dialog box similar to the one below will appear.

Expand the "My Computer" object by clicking on the + next to it. Then select theappropriate network drive that is best to put your documents in.

How to Backup Data if You do not have a network

If you do not have a network and only have a single computer you should periodicallyback up your data. You should purchase or own one of the following:

A read/write CD ROM or DVD drive

A Zip drive

A tape drive - Usually these are more expensive.

You should be aware of where you store your files and you should also know where yourmail files are stored by your mail program such as Outlook or Outlook Express. If youright click on your inbox folder in Outlook Express you can find the location where yourmail is stored. On my system it is stored in the folder at: C:\Documents andSettings\Username\Local Settings\ApplicationData\Identities\{B718C535-6548-4E1D-A5D2-7D1B41CFEB2E}\Microsoft\OutlookExpress\ where username is the name I login with. If you are using Outlook, it is normallystored in a file of type .pst and on my system it is in the folder C:\Documents andSettings\Username\Local Settings\Application Data\Microsoft\Outlook\ where Username isthe name I login with.

Setting up a Backup Job

To open the Windows backup program on Windows 2000, select Start, then Programs,then Accessories, then System Tools, then Backup. You must be a backup operator oradministrator on your system to create a backup job. The backup utility will start asshown below.

Immediate Backup

If you want to do an immediate backup, click on the Backup tab and select the files thatyou want to backup. On my system I selected the folders C:\Documents andSettings\Username\Local Settings\Application Data\Identities\, C:\Documents andSettings\Username\Local Settings\Application Data\Microsoft\Outlook\, and other areaswhere I store my data such as "My Computer". Also be sure to check the box next to"System State" which may save you a lot of grief if you have trouble with your system.

Click on the "Start backup" button and on the dialog box that appears select either"Append..." or "Replace..." data on the media, then select "Start Backup".

Schedule a Backup

To schedule a backup, click on the "Schedule Backups" tab. The Backup program willshow a calendar as shown below.

Click the "Add Job" button. A backup wizard will start. Click "Next". A "What to backup"dialog box as shown below will appear.

Select "Backup selected files, drives, or network data" and click "Next". On the next boxselect the items you want to backup by first clicking the + next to "My Computer" toexpand it as shown below.

Select the items in the same way as discussed under the header called "ImmediateBackup" above and click Next. The dialog box will change and allow you to select thename and location of the file the backup will be stored in. Click "Next" and a dialog boxwill ask the type of backup you want to perform. A normal backup will be sufficient soselect it unless you have another preference and click "Next". You can read more aboutthe backup types at the Windows NT File Backup Page.

After clicking next, select "Verify data after backup" and click "Next". Select whether toAppend or replace data if the file already exixst at the specified location and click "Next".Accept or specify the backup label and click "Next". The below dialog box will appear.

Click on the "Set Schedule button and the dialog box below will appear.

Select your preferred backup times and how often you want to do this backup such asweekly. Click OK and the backup schedule dialog box will disappear. Enter the name ofyour backup job and click next on the "When to back up" dialog box. Click "Finish" tocomplete the process. Backups should run when you have scheduled them.

If you want to delete a backup job that you have scheduled, click on the "Schedule Jobs"tab and click on the job shown on the calendar. A dialog box with the job name will popup. You can click on the "Delete" button next to the Job name to delete the Job.

PHASE V: SECURITY

Lesson XIV: Viruses and Worms

In general terms a virus is a program that runs on a system against the owner's or user'swishes and knowledge. Viruses have one or more methods they use to spread. Mostcommonly they will attach a file to an e-mail message and attempt to trick victims intorunning the attachment.

Virus Damage

In most cases, viruses can do any amount of damage the creator intends them to do.They can send your data to a third party and then delete your data from your computer.They can also ruin your system and render it unusable without a re-installation of theoperating system. Most have not done this much damage in the past, but could easily dothis in the future. Usually the virus will install files on your system then will change your

system so the virus is run every time you start your system. It will then attempt toreplicate itself by sending itself to other potential victims.

The normal effect a virus will have on your system is that over time your system will runslower. Also when you are using the internet your connection may seem to run slower.Eventually you may have trouble running programs on your system, your system mayfreeze, and in the worst case you may not be able to get it to boot up when you turn yourcomputer on.

How Viruses or Worms Spread

Most commonly viruses today use e-mail to spread however they have used one or moreof the following methods to spread in the past.

Some viruses will load themselves onto any part of a writable removable drive aspossible and spread from computer to computer as people use the removable drive.

A worm is a program similar to a virus that will exploit a vulnerability in anoperating system or application that a computer user is running. The best defenseagainst a worm is to have either a personal firewall on your system or be behind acorporate firewall. Another good defense is to update your system regularly. All youneed to do to get a worm is to connect an unpatched computer to the internet orinfected network when your computer does not have firewall protection.

Most viruses will spread themselves using e-mail attachments. They may tell theuser that they neet to open the attachment to get the rest of the information that isbeing sent to them. Many times the virus may claim it is an administrator and theuser needs to either read the data or install a program on their system. Viruseshave even claimed to be Microsoft sending a system patch as an attachment to thee-mail. Microsoft would never send a system patch through e-mail.

Lesson XV: Worms and Prevention

Since worms spread by taking advantage of vulnerabilities in operating systems orapplication programs (remember from earlier discussion, vulnerabilities are softwareerrors that allow some kind of unauthorized access when they are used or exploited). Youdo not need to do anthing special to get a worm except to connect to the internet or aninfected network with a system that has vulnerabilities. There are several good defensesagainst worms.

What is a Firewall?

A firewall is a device that limits access to your system from the outside. A firewall may bea software program running on your computer or it may be a piece of hardware outsideyour computer. The firewall screens any attempts to access your system and only allowsaccess that you decide to allow. In this way many vulnerabilities that could be used togain unauthorized access to your system are eliminated.

Worm Prevention

There are three defenses against worms. They are as follows:

A personal firewall should be run on any system that is not behind a corporatefirewall. This should be done on any computer that connects to the internet even ifthe connection it uses is a slow dial up connection.

Patching your system with updates to fix the vulnerabilities. Patching is the act ofdownloading updates to the vulnerable operating system or application andapplying the update to the program.

Continually running anti-virus software which may detect worms. This is not thebest defense against worms however because sometimes the worm can infect thesystem before the anti-virus software can detect it.

Of the above measures the first two are the most effective against worms. For moreinformation about personal firewalls, why you should use them, and how you can updateyour system, see the Home Computer Security article on this site.

Lesson XVI: Securing Your System

There are several measures which you can take to secure your system. The first and mostimportant is to become informed about how your system works and what the threats are.Reading this guide and acting on the tips contained here is a good start.

Personal firewall - If you are not behind a corporate firewall, purchase and install apersonal firewall on your computer. This will help protect your system from manyvulnerabilities that some worms will try to exploit.

Updates - Perform system updates often. You can go to the Windows Update site todownload updates for your system. Another way to get updates if your system isrunning Windows 2000 or Windows XP is to configure your system to downloadautomatic updates. This can be done by opening your control panel (Click on"Start", then select "Settings", and click on "Control Panel". To configure updatesdouble click the "Automatic Updates" icon and choose one of three configurations.

Use anti-virus software with regular updates. Be sure to run anti-virus software anddownload updates at least twice per week. There are many brands of anti-virussoftware which may be purchased at your local computer, office supply store, or onthe internet. I will not be recommending any name brands in this tutorial.

Be aware of how viruses spread and don't open attachments unless you are SUREthey are legitimate. Call the sender if necessary to be sure they sent the email. Besure your system settings are set so you can recognize potential virus files thatmay have multiple extensions such as filename.txt.exe. If the extension ends in.exe, .com, or .bat don't double click on it or run it unless you are SURE it is from alegitimate source.

Avoid installing bad applications. As mentioned in the section about applicationprograms, some computer programs may come with spyware or adware. Avoidingthese can be important in both securing your system and keeping your systemperformance from being degraded. Keep in mind that adware programs maydownload and install other programs from the internet. A personal firewall is onedefense against this happening because it will normally notify you when a programaccesses the internet.

Configure your system so you will see all file extensions as described on the pagecalled "Windows File View Settings".

For more information about the security measures you should take, see the HomeComputer Security article on this site.

PHASE VI: EMAIL

Lesson XVII: Internet Email

The Internet Email System

The email system that is currently used on the internet was not designed to curb theabuses presented by viruses and SPAM as they are occurring today. The email systemtoday allows:

Anyone can set the "From" field in the email to any value they want. This meansthat you can send an email message and make it look like the President of theUnited States sent the message. There are ways to tell that this is not the case, buton the surface it will appear like the President of the United States sent themessage. This is called faking the sending address.

If an email cannot be delivered, the email standard provides for the sender toreceive a notification indicating that the message could not be delivered. Someemail servers are also set up to notify the sender when a virus is found in an emailthey sent.

There are several things that the email system in use today does not provide for:

The system does not provide for positive identification of the sender.

There is no method to prevent a sender from sending unwanted emails.

Email Problems

Given the above conditions, several problems can occur.

If the sending address of the email is faked, any messages indicating the messagecould not be delivered will go to the person who appears to have sent the emailrather than the person who actually sent it. This can cause people to receive nondeliverable notifications for emails that they did not send which can be veryconfusing.

If a virus sends an email with a faked sender address, a mail server may detect thevirus in the message and send a reply to the faked address notifying someone thatthey sent an email with a virus in it when in fact they did not. This can causeconfusion and waste administrators time since users may call administrators andwant their systems checked for viruses when they are not acutally infected with avirus. This is why administrators of mail servers should turn off notifications toaddresses that appear to have sent a virus.

Someone can fake the sender of an email and send embarrassing or annoyingmessages and possibly jeopardize the reputation of the party they are sending the

email as. They can make it appear as though a reputable party is sending smut onthe internet. I do not know if there are any laws against this, but there should be.This would be called fraud along with some possible other charges such as libel andslander. There are ways to tell that the sender did not actually send the email butthis could still unjustly hurt someone's reputation.

Recipients of virus or SPAM emails are unwilling recipients. These emails tie up theirtime and computer resources. When someone pays for a connection to the internet,and this connection is used to send them unwanted emails, this is the same as adenial of service attack and is essentially stealing. Everyone who connects to theinternet has the right to use their connection haw they want and not how someoneelse wants. I will talk more about this in the section about SPAM.

Lesson XVIII: Email Viruses

E-mail Viruses

Viruses that spread through e-mail have a common method of spreading. This page willdiscuss how common e-mail viruses currently spread.

The Virus Lifecycle

Viruses begin their life when someone releases them on the internet. They begin tospread. At this early stage of their lifecycle, no one is aware of their presence. As the virusbecomes more widely spread, someone will recognize an abnormal problem with theirsystem and investigate. Eventually a computer expert will conclude that a virus exists andnotify companies that write anti virus software. The companies will research the virus andcome out with an update to their database of viruses that includes information about thenew virus and has information about how to recognize it. They may also release a toolthat can be used to automatically remove that virus from computer systems.

Therefore the cycle is:

1. Release - The virus is released.

2. Recognition - Someone recognizes the virus.

3. Virus recognition database update - Antivirus programs will now recognize thevirus.

4. Antivirus update and removal tools

The time between step one and step three above can be significant. During this time youare vulnerable to getting the virus because your anti-virus software will not recognize it asa virus. This is why you should be careful about the e-mail attachments that you open,even if you are actively running anti-virus software.

How Viruses Work

1. When a victim of a virus double clicks on an infected attachment, the virus will run.

2. The virus will modify the victim's system so it will always be active when the systemis turned on.

3. The virus will scan the victim's address book in their e-mail client program such asOutlook or Outlook Express.

4. In the past, viruses would then mail themselves to addresses found in the victim'saddress book. But today many viruses choose random recipients and senders fromthe victim's address book. This means that although the e-mail is sent from thevictim's machine, the e-mail sender address is faked to appear as though someoneelse in the victim's address book sent the message.

What to Do

Always run anti-virus software and be sure it gets updated at least twice per week.

If you get a virus in an e-mail attachment and you are sure it is a virus, delete thee-mail message.

If you get an attachment from someone you know, consider whether there isenough personal information in the e-mail which a virus program would not know.If you are not sure your acquaintance sent the e-mail call them and be sure beforeopening the attachment. Do not count on your anti-virus software being able tostop you from getting infected if you open the e-mail attachment. Remember,viruses are not recognized right away by your anti-virus software and you could geta new unrecognized virus before your virus definition updates are released.

If you get an e-mail saying a message you sent was undeliverable and you did notsend the message, consider whether your system is behaving abnormally. Youprobably do not have a virus, but if you are not sure, use your anti-virus softwareto perform a system scan for viruses and remove any viruses found using theprocedure in the section about "Removing Viruses", then delete the e-mail.

If you get an e-mail saying a message you sent contained a virus, consider whetheryour system is behaving abnormally. You probably do not have a virus, but if youare not sure, use your anti-virus software to perform a system scan for viruses andremove any viruses found using the procedure in the section about "RemovingViruses", then delete the e-mail.

Example

Below is shown an e-mail from a virus as an example of how a virus writer will try to foolcomputer users.

From: staff@yourorganization.org [mailto:staff@yourorganization.org]Sent: Wednesday, March 03, 2004 4:41 AMTo: usertofool@yourorganization.orgSubject: Important notify about your e-mail account.

Dear user of e-mail server "Yourorganization.org",

Our antivirus software has detected a large amount of viruses outgoingfrom your email account, you may use our free anti-virus tool to clean upyour computer software.

For further details see the attach.

For security reasons attached file is password protected. The password is"22352".

Cheers, The Yourorganization.org team http://www.yourorganization.org

Of course there is an attachment. In this case the virus sent a zipped file (.zip) andinstructed the user how to open it. It was encrypted in a zipped file so the anti-virusscanner could not detect it!

Lesson XIX: Spam

Spam is unsolited junk e-mail sent to large numbers of e-mail addresses. It is used topromote some product or service and many spam e-mails are pornographic in nature.

Spam Prevention

Unfortunately there are not very many good ways of preventing spam other than keepingyour e-mail address secret. It should be kept at a level of security somewhere betweenyour phone number and your social security number. You should be careful about whoyou give your email address to. Many companies will sell your email address to spam lists,thus making it available to spammers.

I currently use three email accounts as follows.

The first account is the one I give to personal acquaintances.

The second account I give to companies that have a privacy policy that I am fairlycertain won't sell my e-mail address.

The third account, I give to companies that I believe I cannot trust to sell myinformation. I don't worry if these companies can contact me.

expect to change the third account pretty often, but hopefully the first two will last severalyears without much spam. The third account may be through a free internet emailaccount service such as hotmail or yahoo.

Managing Spam

Besides keeping your e-mail address secret, the next best spam relief are programs thathelp you manage spam. Spam can be filtered at the mail server with some programs orthey can be a program that plugs into your e-mail client program such as Outlook orOutlook Express. Basically these types of programs filter spam based on severalcharacteristics such as:

The subject line

The address of the sender

Some programs scan the message content and consider length or wording.

Unfortunately none of these scanning methods are 100% accurate although some claim toachieve success rates into the upper 90 percentile. What most of these programs do is tocreate folders for "friendly" mail or "unfriendly" mail. The friendly mail is put into onefolder, unfriendly mail is put into a second folder and there may be a third folder forunknown mail. Unfriendly mail is automatically deleted after some period of time. Thecapabilities and handling of the mail will vary from program to program. Some that I haveconsidered using include:

Qurb

I Hate Spam

Spam Assassin

There are various opinions about what works when fighting spam. For more informationand articles about how to fight spam you can find links to articles at Computer TechnicalTutorials Spam .

Spam for Webmasters

If you are a webmaster, spammers will send spam to your domain by sending it togeneral possible accounts such as administration@yourdomain.com. One way to preventthis is to configure your account with your hosting provider not to respond toundeliverable emails and just automatically delete them. This is called a "::blackhole"setting. The only problem with this is that spammers will still use your bandwidth that youpay for to send you their junk, even though your server deletes them. As spam gets moreexcessive, it may increase bandwidth costs for webmasters thus discouraging some sitesfrom operating.

Why Spam Should be Illegal

When you connect to the internet, you are paying for a specific service for your use. Thisservice costs a specific amount of money and provides a certain connection speed to theinternet. This connection speed indicates your bandwidth. The greater the connectionspeed, the higher the bandwidth. The higher speed connections cost more money. At thispoint you have paid for the privilege of surfing the internet with your web browser,sending and receiving e-mail, and other activities. The speed at which you can do this islimited by your bandwidth and how fast you can click pages or send or receive e-mail.Consider the Following diagram:

Each person has a connection to the internet. If the person on the right chooses to usetheir connection to send e-mail or junk e-mail (spam), that is their choice. They arepaying for their connection and they are willing to use it in that manner.

If the person on the left does not want to receive spam, but wants to read personal e-mailand surf the internet, they are willing to receive only personal e-mail. If someone issending them a lot of spam, they will need to wait for the junk e-mail to be deliveredbefore they can read much of their personal e-mail. They are an unwilling participantregarding the unsolicited e-mail they are receiving. Not only is their connection being usedby someone else, but it will take them additional time to sort the mix of e-mail out to getto the mail they want to read. If the receiver had willingly stated that they were interestedin receiving the advertisements, it would be another matter.

Of course the sender of the spam is not using all the spam receiver's internet connection,but the spam receiver does not get the opportunity to use their connection in the waythey fully intended even though they were the one paying for it. This is the same asstealing even though the effective amount may be small. Imagine, how rich you could beif you could only steal a fraction of a cent per day or week from everyone who uses theinternet. That's why spam should be illegal.

Someone may argue that spam is the same as junk mail sent through the postal serviceso why would it be stealing. This is not true since the sender of mail through the postalservice pays for the cost of both pickup and delivery. On the internet, the sender pays forthe cost of pickup and the receiver pays for the cost of delivery.

The Real and Permanent Solution to Spam and Viruses

Unfortunately a permanent and good solution will take years to implement. A new mailprotocol (method of sending e-mail) must be developed by the internet community andthen e-mail servers must be modified to handle that protocol. The changing of the e-mailservers will take the most time.

I believe all e-mail should be digitally signed by the sender in order to be delivered. Thisway the sender cannot be faked and everyone must take responsibility for their owne-mails. However to get this to work right someone must find a way to keep viruses frombeing able to digitally sign your e-mails for you automatically. A bug in your e-mail client

may allow a virus to digitally sign your e-mails causing this type of solution to beineffective, however, in this case, there would be no doubt as to who has the virus.

Some Proposed Solutions that Won't Work

Paying for each e-mail sent - This solution will not work because it forces people topay for services that they have already paid for. Additionally it will not preventspammers from using poorly configured servers to send spam illegally. It will mostlikely force victims (those who get viruses and administrators who have spammersillegally relay mail through their mail servers) to pay for the additional e-mail. Onthe brighter side, it may force more administrators to lock their systems downbetter and force computer users to be more careful about getting viruses. If thiswere done, I would think it would make the most sense to allow a limited amount ofemail to be send on a monthly basis for free.

Reverse address to name lookup - Some ISP's want to use a check that looks at theaddress the mail came from and determine the name of the server. If the namedoes not match the name advertised by the sending mail server, then the e-mail isassumed to be spam and dropped with no notification to the sender. Not only doesthis violate the rules (protocol) governing the internet for sending e-mail, it will cutdown or eliminate the ability for web based programs to automatically notify usersat some websites about events. For instance forum sites will notify when someonehas posted an answer to a question. If the user's ISP uses reverse lookup, the usermay never see the email from the forum website where they asked a question.

PHASE VII: General

Lesson XX: Removing Viruses

Removing viruses can be risky to your operating system and may cause you to need tore-install your operating system. If you do not feel comfortable with the instructions inthis section, you should get a computer professional to do the job. For more informationread Applying the latest patches to your Windows 2000 Operating system to preventviruses and worms. It contains information about how to remove viruses along with otheruseful information.

Virus Removal Procedure

1. Be sure you have good backups of your data along with an emergency boot disk foryour system.

2. Determine what viruses you have on your system.

1. Install a virus scanning program if you do not have one already installed. Usethe product of your choice. It is wise to read product reviews.

2. Be sure your virus definitions are up to date. Connect to the internet anddownload the latest virus definitions from the company that created youranti-virus software.

3. Configure your virus scanner not to remove any viruses but only detectthem. You do not want to remove the virus(es) immediately since someviruses may infect files that your system requires to run. If these files cannot

be cleaned by the anti-virus program, they may be deleted or quaranteened.If this happens you may not be able to run your system again.

4. Scan for viruses but do not remove them. Note: Some viruses will stop yourvirus scanner from operating. If this is the case you will probably need thehelp of a computer professional. If you have a virus that stops your virusscanner then you will need to either share the drive across a network andscan it from another computer or remove your hard drive and place it intoanother computer as a second hard drive, then scan your hard drive.

3. Learn about the viruses you have and how to remove them. - Go to the web site ofthe organization that created your anti-virus software. The Symantec securityresponse site is a good site to find information about specific viruses and theyprovide virus removal tools.

4. Remove the viruses.

1. Many viruses have a removal tool which can be used to remove the virus. Ifthere is a removal tool, download it and use it to remove the virus.

2. If there is no removal tool, you will need to follow the manual removalinstructions. You may need to manually delete virus files and edit yoursystem registry. The removal instructions will tell you how to do this, butsome people may not feel comfortable doing this without the help of acomputer professional.

3. If the manual instructions indicate that you should let your virus scannerremove the virus, then remove all viruses that you can with virus removaltools then run the virus scanner with it configured to remove all viruses.

Lesson XXI: Making a Boot Disk

Open the Windows backup program on Windows 2000 by selecting Start, then Programs,then Accessories, then System Tools, then Backup. The backup utility will start as shownbelow.

When the Welcome tab is displayed in the Backup program, click on the "EmergencyRepair Disk" button near the bottom. When the "Emergency Repair Diskette" dialog boxappears select the checkbox next to "Also backup the registry to the repair directory..."and click OK. You will need to put a blank floppy into your floppy disk drive.

Once the process is complete, you should label the floppy disk with the current date andthe name of the system you are making the disk for.

If you ever get into a situation where your system will not boot, you can use this disk tohelp you recover your system. This is a somewhat technical process but it begins by

pressing the F8 function key while the system is booting which will provide someadvanced booting options, one of which will allow you to try to boot using your emergencyrepair disk. It is usually much easier to recover a system that has an emergency repairdisk.

Lesson XXII: Summary

There are several things you should do to make your system more secure, and keep itperforming better:

Change your file view settings on Windows systems so you will see all fileextensions.

Always run anti-virus software and keep the virus definitions updated at least twiceper week.

Never connect to the internet unless you are using a personal firewall or are behindan organizational firewall on a private network.

Never open e-mail attachments without being sure of who sent them. Keep thefollowing in mind:

E-mail addresses can be faked by virus programs.

New viruses may not be recognized by your anti-virus software.

Patch your operating system regularly. This will reduce your vulnerabilities toworms and hackers. See the Applying the latest patches to your Windows 2000Operating system to prevent viruses and worms article for more information.

Patch your applications regularly especially Microsoft Office. See the PreventingViruses in Microsoft Office® Products article for more information.

Perform regular backups of your data.

Make an emergency boot disk to enable you to restore your system in the event offile corruption or a virus that makes it unable to boot.

Avoid installing unneeded applications and always be sure any free programs donot have a hidden purpose.

PHASE VIII: APPENDICES

Lesson XXIII: Terms

Basic Computer Terms

Bit - A binary unit of data storage that can only be a value of 0 or 1.

BIOS - BIOS stands for Basic Input/Output System and it is a low level programused by your system to interface to computer devices such as your video card,keyboard, mouse, hard drive, and other devices.

Boot - A term used to describe what happens to a computer when it is turned on,the operating system begins to run, and then the user is able to use the computersuccessfully.

Byte - 8 bits of data which has a possible value from 0 to 255.

CD-ROM disk - A disk with about 640Mb of storage capacity which are morecommonly read than written to.

CD-ROM drive - The hardware component that is used to read a CD-ROM or writeto it.

Crash - A common term used to describe what happens to a computer whensoftware errors force it to quit operating and become unresponsive to a computeruser.

Driver - A specially written program which understands the operation of the deviceit interfaces to, such as a printer, video card, sound card or CD ROM drive. Itprovides an interface for the operating system to use the device.

File - A collection of data into a permanent storage structure. Stored on apermanent storage media such as a computer hard drive.

Firmware - Software written into permanent storage into the computer.

Floppy disk - A low capacity storage media which can be written to as easily as it isread.

Floppy Drive - The hardware component that is used to read or write to a floppydisk.

Hardware - Describes the physical parts of your computer which you can physicallytouch or see such as your monitor, case, disk drives, microprocessor and otherphysical parts.

Internet - A network of networks which incorporate a many organizations, physicallines, the ability to route data, and many services including email and webbrowsing.

ISP - Internet Service Provider is an organization that provides the ability toconnect to the internet for their customers. They also usually provide additionalservices such as e-mail and the ability to host web sites.

MIME - multipurpose internet mail extension

Memory - Used to provide the temporary storage of information function.

Network - A general term describing to the cables and electronic components thatcarry data between computers. It is also generally used to refer to the servercomputers that provide services such as printing, file sharing, e-mail, and otherservices.

Operating System - The core software component of a computer providing theability to interface to peripheral and external devices along with program functionsto support application programs.

Parallel - A data transmission method where data is sent on more than one line at atime. This may be any number of bits at a time, but is usually one word at a time(two bytes) or possibly three bytes at a time.

Protocols - A standard method used for communications or other internet andnetwork functions.

Security flaw - A software bug allowing an attacker a method to gain unauthorizedaccess to a system.

Serial - A data transmission method where data is sent on a single line and one bitis sent at a time. This is similar to a line which one item must come one afteranother

Software - Describes the programs that run on your system.

SPAM - A term used to describe junk and unsolicited e-mail.

Storage Media - A term used to describe any magnetic device that computer datacan be permanently stored on such as a hard drive or floppy drive.

URL - Uniform Resource Locator is the term used to describe a link which points toa location of a file on the internet.

Virus - A program that runs on a system against the owner's or user's wishes andknowledge and can spread by infecting files or sending itself through e-mail

Vulnerability - Software errors that allow some kind of unauthorized access whenthey are used or exploited.

Word - Two bytes or 16 bits of data with a possible unsigned value from 0 to16535.

Worm - A term used to describe an unwanted program that uses system orapplication vulnerabilities to infect a computer without the user doing anything butconnecting to an infected network.