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Antivirus softwareAntivirus, anti-virus, or AV software is computer software used to prevent, detect and remove malicious computerviruses. Most software described as antivirus also works against other types of malware, such as malicious BrowserHelper Objects (BHOs), browser hijackers, ransomware, keyloggers, backdoors, rootkits, trojan horses, worms,malicious LSPs, dialers, fraudtools, adware and spyware.[1] Computer security, including protection from socialengineering techniques, is commonly offered in products and services of antivirus software companies. This pagediscusses the software used for the prevention, detection, and removal of malware threats, rather than computersecurity implemented by software methods.A variety of strategies are typically employed. Signature-based detection involves searching for known patterns ofdata within executable code. However, it is possible for a computer to be infected with new malware for which nosignature is yet known; and malware is often modified to change its signature without affecting functionality. Tocounter such so-called zero-day threats, heuristics can be used. One type of heuristic approach, generic signatures,can identify variants by looking for slight variations of known malicious code in files. Some antivirus software canalso predict what a file will do by running it in a sandbox and analyzing what it does to see if it performs any actionswhich could be malicious.Antivirus software has some drawbacks. It can impair a computer's performance. Inexperienced users can be lulledinto a false sense of security when using the computer, considering themselves to be totally protected, and may haveproblems understanding the prompts and decisions that antivirus software presents them with. An incorrect decisionmay lead to a security breach. If the antivirus software employs heuristic detection, it must be fine-tuned to minimizemisidentifying harmless software as malicious (false positive). Antivirus software itself usually runs at the highlytrusted kernel level of the operating system to allow it access to all potential malicious process and files, creating apotential avenue of attack.

History

An example of free antivirus software: ClamTk3.08.

Most of the computer viruses written in the early and mid-1980s werelimited to self-reproduction and had no specific damage routine builtinto the code.[2] That changed when more and more programmersbecame acquainted with virus programming and created viruses thatmanipulated or even destroyed data on infected computers.

There are competing claims for the innovator of the first antivirusproduct. Possibly the first publicly documented removal of a computervirus in the wild was performed by Bernd Fix in 1987.[3] There werealso two antivirus applications for the Atari ST platform developed in1987. The first one was G Data and second was UVK 2000.

Fred Cohen, who published one of the first academic papers oncomputer viruses in 1984,[4] began to develop strategies for antivirus software in 1988[5] that were picked up andcontinued by later antivirus software developers. In 1987, he published a demonstration that there is no algorithmthat can perfectly detect all possible viruses.[6]

In 1987 the first two heuristic antivirus utilities were released: Flushot Plus by Ross Greenberg and Anti4us byErwin Lanting. [citation needed]

Also in 1988 a mailing list named VIRUS-L[7] was started on the BITNET/EARN network where new viruses and the possibilities of detecting and eliminating viruses were discussed. Some members of this mailing list like John McAfee or Eugene Kaspersky later founded software companies that developed and sold commercial antivirus

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software.Before internet connectivity was widespread, viruses were typically spread by infected floppy disks. Antivirussoftware came into use, but was updated relatively infrequently. During this time, virus checkers essentially had tocheck executable files and the boot sectors of floppy disks and hard disks. However, as internet usage becamecommon, viruses began to spread online.Over the years it has become necessary for antivirus software to check an increasing variety of files, rather than justexecutables, for several reasons:• Powerful macros used in word processor applications, such as Microsoft Word, presented a risk. Virus writers

could use the macros to write viruses embedded within documents. This meant that computers could now also beat risk from infection by opening documents with hidden attached macros.

•• The possibility of embedding executable objects inside otherwise non-executable file formats can make openingthose files a risk.

• Later email programs, in particular Microsoft's Outlook Express and Outlook, were vulnerable to virusesembedded in the email body itself. A user's computer could be infected by just opening or previewing a message.

As always-on broadband connections became the norm, and more and more viruses were released, it becameessential to update virus checkers more and more frequently. Even then, a new zero-day virus could becomewidespread before antivirus companies released an update to protect against it.

Identification methodOne of the few solid theoretical results in the study of computer viruses is Frederick B. Cohen's 1987 demonstrationthat there is no algorithm that can perfectly detect all possible viruses.There are several methods which antivirus software can use to identify malware:• Signature based detection is the most common method. To identify viruses and other malware, antivirus software

compares the contents of a file to a dictionary of virus signatures. Because viruses can embed themselves inexisting files, the entire file is searched, not just as a whole, but also in pieces.

• Heuristic-based detection like malicious activity detection, can be used to identify unknown viruses.• File emulation is another heuristic approach. File emulation involves executing a program in a virtual

environment and logging what actions the program performs. Depending on the actions logged, the antivirussoftware can determine if the program is malicious or not and then carry out the appropriate disinfection actions.

Signature-based detectionTraditionally, antivirus software heavily relied upon signatures to identify malware. This can be very effective, butcannot defend against malware unless samples have already been obtained and signatures created. Because of this,signature-based approaches are not effective against new, unknown viruses.As new viruses are being created each day, the signature-based detection approach requires frequent updates of thevirus signature dictionary. To assist the antivirus software companies, the software may allow the user to upload newviruses or variants to the company, allowing the virus to be analyzed and the signature added to the dictionary.Although the signature-based approach can effectively contain virus outbreaks, virus authors have tried to stay a stepahead of such software by writing "oligomorphic", "polymorphic" and, more recently, "metamorphic" viruses, whichencrypt parts of themselves or otherwise modify themselves as a method of disguise, so as to not match virussignatures in the dictionary.

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HeuristicsSome more sophisticated antivirus software uses heuristic analysis to identify new malware or variants of knownmalware.Many viruses start as a single infection and through either mutation or refinements by other attackers, can grow intodozens of slightly different strains, called variants. Generic detection refers to the detection and removal of multiplethreats using a single virus definition.For example, the Vundo trojan has several family members, depending on the antivirus vendor's classification.Symantec classifies members of the Vundo family into two distinct categories, Trojan.Vundo and Trojan.Vundo.B.While it may be advantageous to identify a specific virus, it can be quicker to detect a virus family through a genericsignature or through an inexact match to an existing signature. Virus researchers find common areas that all virusesin a family share uniquely and can thus create a single generic signature. These signatures often containnon-contiguous code, using wildcard characters where differences lie. These wildcards allow the scanner to detectviruses even if they are padded with extra, meaningless code. A detection that uses this method is said to be"heuristic detection."

Rootkit detectionAnti-virus software can attempt to scan for rootkits; a rootkit is a type of malware that is designed to gainadministrative-level control over a computer system without being detected. Rootkits can change how the operatingsystem functions and in some cases can tamper with the anti-virus program and render it ineffective. Rootkits arealso difficult to remove, in some cases requiring a complete re-installation of the operating system.[8]

Real-time protectionReal-time protection, on-access scanning, background guard, resident shield, autoprotect, and other synonyms referto the automatic protection provided by most antivirus, anti-spyware, and other anti-malware programs. Thismonitors computer systems for suspicious activity such as computer viruses, spyware, adware, and other maliciousobjects in 'real-time', in other words while data loaded into the computer's active memory: when inserting a CD,opening an email, or browsing the web, or when a file already on the computer is opened or executed.[9]

Issues of concern

Unexpected renewal costsSome commercial antivirus software end-user license agreements include a clause that the subscription will beautomatically renewed, and the purchaser's credit card automatically billed, at the renewal time without explicitapproval. For example, McAfee requires users to unsubscribe at least 60 days before the expiration of the presentsubscription while BitDefender sends notifications to unsubscribe 30 days before the renewal. Norton AntiVirus alsorenews subscriptions automatically by default.

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Rogue security applicationsSome apparent antivirus programs are actually malware masquerading as legitimate software, such as WinFixer, MSAntivirus, and Mac Defender.

Problems caused by false positivesA "false positive" is when antivirus software identifies a non-malicious file as a virus. When this happens, it cancause serious problems. For example, if an antivirus program is configured to immediately delete or quarantineinfected files, a false positive in an essential file can render the operating system or some applications unusable. InMay 2007, a faulty virus signature issued by Symantec mistakenly removed essential operating system files, leavingthousands of PCs unable to boot. Also in May 2007, the executable file required by Pegasus Mail was falselydetected by Norton AntiVirus as being a Trojan and it was automatically removed, preventing Pegasus Mail fromrunning. Norton AntiVirus had falsely identified three releases of Pegasus Mail as malware, and would delete thePegasus Mail installer file when that happened. In response to this Pegasus Mail stated:

“On the basis that Norton/Symantec has done this for every one of the last three releases of Pegasus Mail, we can only condemn this product astoo flawed to use, and recommend in the strongest terms that our users cease using it in favour of alternative, less buggy anti-virus packages.”

In April 2010, McAfee VirusScan detected svchost.exe, a normal Windows binary, as a virus on machines runningWindows XP with Service Pack 3, causing a reboot loop and loss of all network access.In December 2010, a faulty update on the AVG anti-virus suite damaged 64-bit versions of Windows 7, rendering itunable to boot, due to an endless boot loop created.In October 2011, Microsoft Security Essentials (MSE) removed the Google Chrome web browser, rival toMicrosoft's own Internet Explorer. MSE flagged Chrome as a Zbot banking trojan.When Microsoft Windows becomes damaged by faulty anti-virus products, fixing the damage to Microsoft Windowsincurs technical support costs and businesses can be forced to close whilst remedial action is undertaken.

System and interoperability related issuesRunning multiple antivirus programs concurrently can degrade performance and create conflicts. However, using aconcept called multiscanning, several companies (including G Data and Microsoft) have created applications whichcan run multiple engines concurrently.It is sometimes necessary to temporarily disable virus protection when installing major updates such as WindowsService Packs or updating graphics card drivers. Active antivirus protection may partially or completely prevent theinstallation of a major update. Anti-virus software can cause problems during the installation of an operating systemupgrade, e.g. when upgrading to a newer version of Windows "in place" — without erasing the previous version ofWindows. Microsoft recommends that anti-virus software be disabled to avoid conflicts with the upgrade installationprocess.[10][11]

The functionality of a few computer programs can be hampered by active anti-virus software. For exampleTrueCrypt, a disk encryption program, states on its troubleshooting page that anti-virus programs can conflict withTrueCrypt and cause it to malfunction or operate very slowly. Anti-virus software can impair the performance andstability of games running in the Steam platform.[12]

Support issues also exist around antivirus application interoperability with common solutions like SSL VPN remoteaccess and network access control products.[13] These technology solutions often have policy assessmentapplications which require that an up to date antivirus is installed and running. If the antivirus application is notrecognized by the policy assessment, whether because the antivirus application has been updated or because it is notpart of the policy assessment library, the user will be unable to connect.

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EffectivenessStudies in December 2007 showed that the effectiveness of antivirus software had decreased in the previous year,particularly against unknown or zero day attacks. The computer magazine c't found that detection rates for thesethreats had dropped from 40-50% in 2006 to 20-30% in 2007. At that time, the only exception was the NOD32antivirus, which managed a detection rate of 68 percent.The problem is magnified by the changing intent of virus authors. Some years ago it was obvious when a virusinfection was present. The viruses of the day, written by amateurs, exhibited destructive behavior or pop-ups.Modern viruses are often written by professionals, financed by criminal organizations.Independent testing on all the major virus scanners consistently shows that none provide 100% virus detection. Thebest ones provided as high as 99.9% detection for simulated real-world situations, while the lowest provided 91.1%in tests conducted in August 2013. Many virus scanners produce false positive results as well, identifying benignfiles as malware.Although methodologies may differ, some notable independent quality testing agencies include AV-Comparatives,ICSA Labs, West Coast Labs, Virus Bulletin, AV-TEST and other members of the Anti-Malware Testing StandardsOrganization.[14]

New virusesAnti-virus programs are not always effective against new viruses, even those that use non-signature-based methodsthat should detect new viruses. The reason for this is that the virus designers test their new viruses on the majoranti-virus applications to make sure that they are not detected before releasing them into the wild.Some new viruses, particularly ransomware, use polymorphic code to avoid detection by virus scanners. JeromeSegura, a security analyst with ParetoLogic, explained:

“It's something that they miss a lot of the time because this type of [ransomware virus] comes from sites that use a polymorphism, which meansthey basically randomize the file they send you and it gets by well-known antivirus products very easily. I've seen people firsthand gettinginfected, having all the pop-ups and yet they have antivirus software running and it's not detecting anything. It actually can be pretty hard toget rid of, as well, and you're never really sure if it's really gone. When we see something like that usually we advise to reinstall the operatingsystem or reinstall backups. ”

A proof of concept virus has used the Graphics Processing Unit (GPU) to avoid detection from anti-virus software.The potential success of this involves bypassing the CPU in order to make it much harder for security researchers toanalyse the inner workings of such malware.[15]

RootkitsDetecting rootkits is a major challenge for anti-virus programs. Rootkits have full administrative access to thecomputer and are invisible to users and hidden from the list of running processes in the task manager. Rootkits canmodify the inner workings of the operating system[16] and tamper with antivirus programs.

Damaged filesFiles which have been damaged by computer viruses are normally damaged beyond recovery. Anti-virus softwareremoves the virus code from the file during disinfection, but this does not always restore the file to its undamagedstate. In such circumstances, damaged files can only be restored from existing backups; installed software that isdamaged requires re-installation (however, see System File Checker).

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Firmware issuesActive anti-virus software can interfere with a firmware update process. Any writeable firmware in the computer canbe infected by malicious code. This is a major concern, as an infected BIOS could require the actual BIOS chip to bereplaced to ensure the malicious code is completely removed. Anti-virus software is not effective at protectingfirmware and the motherboard BIOS from infection.

Other methods

A command-line virus scanner, Clam AV 0.95.2,running a virus signature definition update,

scanning a file and identifying a Trojan

Installed antivirus software running on an individual computer is onlyone method of guarding against viruses. Other methods are also used,including cloud-based antivirus, firewalls and on-line scanners.

Cloud antivirus

Cloud antivirus is a technology that uses lightweight agent software onthe protected computer, while offloading the majority of data analysisto the provider's infrastructure.One approach to implementing cloud antivirus involves scanningsuspicious files using multiple antivirus engines. This approach wasproposed by an early implementation of the cloud antivirus conceptcalled CloudAV. CloudAV was designed to send programs or documents to a network cloud where multipleantivirus and behavioral detection programs are used simultaneously in order to improve detection rates. Parallelscanning of files using potentially incompatible antivirus scanners is achieved by spawning a virtual machine perdetection engine and therefore eliminating any possible issues. CloudAV can also perform "retrospective detection,"whereby the cloud detection engine rescans all files in its file access history when a new threat is identified thusimproving new threat detection speed. Finally, CloudAV is a solution for effective virus scanning on devices thatlack the computing power to perform the scans themselves.

Some examples of cloud anti-virus products are Panda Cloud Antivirus and Immunet.

Network firewallNetwork firewalls prevent unknown programs and processes from accessing the system. However, they are notantivirus systems and make no attempt to identify or remove anything. They may protect against infection fromoutside the protected computer or network, and limit the activity of any malicious software which is present byblocking incoming or outgoing requests on certain TCP/IP ports. A firewall is designed to deal with broader systemthreats that come from network connections into the system and is not an alternative to a virus protection system.

Online scanningSome antivirus vendors maintain websites with free online scanning capability of the entire computer, critical areasonly, local disks, folders or files. Periodic online scanning is a good idea for those that run antivirus applications ontheir computers because those applications are frequently slow to catch threats. One of the first things that malicioussoftware does in an attack is disable any existing antivirus software and sometimes the only way to know of anattack is by turning to an online resource that is not installed on the infected computer.

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Specialist tools

Using rkhunter to scan for rootkits on an UbuntuLinux computer.

Virus removal tools are available to help remove stubborn infections orcertain types of infection. Examples include Trend Micro's RootkitBuster, and rkhunter for the detection of rootkits, Avira's AntiVirRemoval Tool, PCTools Threat Removal Tool, and AVG's Anti-VirusFree 2011.

A rescue disk that is bootable, such as a CD or USB storage device,can be used to run antivirus software outside of the installed operatingsystem, in order to remove infections while they are dormant. Abootable antivirus disk can be useful when, for example, the installedoperating system is no longer bootable or has malware that is resistingall attempts to be removed by the installed antivirus software. Examples of some of these bootable disks include theAvira AntiVir Rescue System, PCTools Alternate Operating System Scanner, and AVG Rescue CD. The AVG RescueCD software can also be installed onto a USB storage device, that is bootable on newer computers.

Usage and risksAccording to an FBI survey, major businesses lose $12 million annually dealing with virus incidents. A survey bySymantec in 2009 found that a third of small to medium sized business did not use antivirus protection at that time,whereas more than 80% of home users had some kind of antivirus installed. According to a sociological surveyconducted by G Data Software in 2010 49% of women did not use any antivirus program at all.

References[1] lifehacker: The Difference Between Antivirus and Anti-Malware (and Which to Use) (http:/ / lifehacker. com/

the-difference-between-antivirus-and-anti-malware-and-1176942277)[2] History of viruses (http:/ / csrc. nist. gov/ publications/ nistir/ threats/ subsubsection3_3_1_1. html)[3] Kaspersky Lab Virus list (http:/ / www. viruslist. com/ en/ viruses/ encyclopedia?chapter=153311150)[4] Fred Cohen 1984 "Computer Viruses – Theory and Experiments" (http:/ / www. eecs. umich. edu/ ~aprakash/ eecs588/ handouts/

cohen-viruses. html)[5] Fred Cohen 1988 "On the implications of Computer Viruses and Methods of Defense" (http:/ / portal. acm. org/ citation. cfm?id=51535)[6] Cohen, Fred, An Undetectable Computer Virus (http:/ / www. research. ibm. com/ antivirus/ SciPapers/ VB2000DC. htm), 1987, IBM[7] VIRUS-L mailing list archive (http:/ / securitydigest. org/ virus/ mirror/ www. phreak. org-virus_l/ )[8] Rootkit (http:/ / www. f-secure. com/ en_EMEA/ security/ virus-removal/ virus-information/ encyclopedia/ encyclopedia_rootkit. html)[9] Kaspersky Lab Technical Support Portal (http:/ / www. kaspersky. com/ faq?chapter=170710015& qid=173727547)[10][10] Mentioned within "Before you begin".[11][11] Mentioned within "General troubleshooting".[12][12] Steam support page.[13] Field Notice: FN - 63204 - Cisco Clean Access has Interoperability issue with Symantec Anti-virus - delays Agent start-up (http:/ / www.

cisco. com/ en/ US/ ts/ fn/ 632/ fn63204. html)[14] Guidelines released for antivirus software tests (http:/ / www. computerworld. com/ s/ article/ 9178037/

Guidelines_released_for_antivirus_software_tests)[15] Researchers up evilness ante with GPU-assisted malware - Coming to a PC near you, by Dan Goodin (http:/ / www. theregister. co. uk/

2010/ 09/ 28/ gpu_assisted_malware/ )[16] GIBSON RESEARCH CORPORATION SERIES: Security Now! (http:/ / www. grc. com/ sn/ sn-009. txt)

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Bibliography• Szor, Peter (2005), The Art of Computer Virus Research and Defense, Addison-Wesley, ISBN 0-321-30454-3

External links• Antivirus software (http:/ / www. dmoz. org/ Computers/ Security/ Malicious_Software/ Viruses/ Products/ ) on

the Open Directory Project

Article Sources and Contributors 9

Article Sources and ContributorsAntivirus software  Source: http://en.wikipedia.org/w/index.php?oldid=597028804  Contributors: 03vaseyj, 16@r, 5theye, A8UDI, AcceleratorX, Aecis, Ahunt, Akhristov, Alansohn,AlistairMcMillan, Altenmann, Although, Ankitguptajaipur, Anonymous Dissident, AntonST, Arichnad, Armando, Arnos78, Arthurnyc, Ashajose0002, Askild, Assumelation, Avun,BENNYSOFT, Babajobu, Badagnani, BazookaJoe, Beetstra, Beland, Bigs slb, Bluerasberry, Boffy b, Bokonon, Borgx, Born2cycle, Bryan Derksen, C45207, Calimero, Cameron Scott,CanadianLinuxUser, CapitalR, CesarB, Chealer, ChongDae, Chris G, Chris the speller, ChrisHodgesUK, Chrisahn, Claunia, CliffC, CommonsDelinker, Conan, Corvus cornix, Courcelles, CraigPemberton, Cumbiagermen, Cuvtixo, CyberSkull, Cybercobra, Cynical, DMWuCg, DabMachine, Dalahäst, DanielPharos, Danny, Dannyruthe, Dark Silver Crow, David Gerard, DavideAndrea,Dawnseeker2000, Delpino, DennisDaniels, DerHexer, Derekcslater, Dfarrell07, Diablosblizz, Diannaa, Diflame, Dimo414, Dinhtuydzao, Dinoguy1000, DirkvdM, Discospinster, Doczilla,DoorsAjar, Dougmarlowe, Downlode, Dunxd, Dwe0008, Dxco, ESkog, Easygoeasycome, Eddymck1, Edward, Egladkih, Eisnel, ElationAviation, Elison2007, Emedlin1, Emenid, Emilinho,Enauspeaker, EncMstr, Eptin, Eran, Erotml, Escape Orbit, Evice, Excirial, Execter, Expertour, FDD, Fabiform, Faizan, Farqad, Femto, Firewall-guy, FleetCommand, Fluffernutter,FluffyWhiteCat, Flyer22, Fourohfour, Franklin.online2006, Frap, Fredtheflyingfrog, Frosted14, Fubar Obfusco, Furrykef, Fæ, G7yunghi, Garamond Lethe, Gary09202000, Gautamcool12,Georgest23, Gilliam, Ginsuloft, Gogo Dodo, Gomm, GraemeL, Grizzly37, Gscshoyru, GunAlchemist, Gurch, Gwernol, Gökhan, HJ Mitchell, HMSSolent, Hagerman, HamburgerRadio,Haseo9999, Hdt83, Heracles31, HexaChord, Hirebrand, Hm2k, Hobart, Hornlitz, Hsinghsarao, Hu12, I am One of Many, IMSoP, Iaen, Ibbn, IceUnshattered, Icenine378, IddiKlu, Ihatetoregister,Immunize, Irfanshaharuddin, Isnow, J.delanoy, J7, JC.Torpey, Jack Greenmaven, Jamesontai, JamieS93, Janendra, Jasper Deng, Javeed Safai, Jaysbro, Jdivakarla, Jerome Charles Potts, Jesant13,Jesse Viviano, Jeza87, JiFish, Jim1138, JoeSmack, John of Reading, JohnLai, JonHarder, JorgePeixoto, Joseph843, JurgenHadley, JuventiniFan, K1ngXSp3c1al, Ka vijay, Kalamkaar, Kandr8,Kbdank71, KellyCoinGuy, Khattab01, Kirill Chiryasov, Kl4m, Korinkami, Kostes32, Kralizec!, Kremnin, Krenair, Kueensrÿche, Kumarworld2, LK20, Lakshmin, Lamarmote, Laudaka,Leahtwosaints, LeaveSleaves, Leedeth, LemonMan, LittleBenW, LizardJr8, Longhair, Lonwolve, Lotje, Lotusv82, Luckas Blade, Lzeltser, Lzur, M.R.V model, MER-C, Ma2001, Makecat,Malijinx, Marnegro, Martarius, Materialscientist, Mathonius, Mats131, Matturn, Mavenkatesh, Meaghan, Mean as custard, Meinsla, Melancholie, Melovfemale, Mentifisto, Mi8ka, Miiszmylove,Mike A Quinn, MikeRS, Mikewax, Mild Bill Hiccup, Mindmatrix, Minesweeper, Miremare, Misi91, Morte, Mortense, Mothmolevna, MrOllie, Mujdat61, Multiwikiswat, Mwtoews, NaBUru38,NawlinWiki, Neon white, Neshemah, Neustradamus, Newmen1020304050, Newspartnergroup, Nightstallion, Nikai, Nisha1987, Noone, Nosferatus2007, Nuno Brito, Ohadgliksman, Omegatron,One666, Oo7jeep, Orbst, Pakaran, Palica, Panda Madrid, Pandawelch, Pastore Italy, PatrickFisher, Patrickjk, Paulsterne, Pavix, Pcguru66, Pedant17, Penubag, Perfecto, Peter, Peterl, Petrb,Phantomnecro, Pharaoh of the Wizards, PhilHibbs, Philip Trueman, Philtweir, Pictureuploader, Piet Delport, Pinethicket, Piotrus, Piyush1992, Pladook, Plati, Pnm, Pol098, Police267,PrimeYoshi, Proland, Public Menace, Qu4rk, Qxz, Raanoo, RainR, Ravensburg13, RedWolf, Redrose64, ReformatMe, Relaxing, RexNL, Rich Farmbrough, Richi, Rick Block, RickK,Ripdog2121, Rjwilmsi, Rlandmann, Roastingpan, Robwingfield, Rockfang, Rohaneknathshinde459, Ronz, Rotring, Rror, Rwmoekoe, Ryan Norton, Ryan889, Ryanxo, S0aasdf2sf, SF007,Sahilm, Saibo, Salvidrim!, Samker, Samwb123, Satellizer, Seam123, Sensiblekid, 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