INTRODUCTIONIn this era of modern technology, computers play a very important role in ourdaily lives Computers play its functions in private homes, offices, workspaces, hospitals,schools, and everywhere else It is undeniable that computers are very importantnowadays but of course, no matter how great the technology is, there will still be someflaws and problems The existence of computer viruses revolutionized the way thecomputer works and what type of security measures are supposed to be taken to prevents serious problem So we provide nod32 key for solving all virus problemWHAT ISA VIRUSAloaded onto yowithout your knowledge and runs against your wishes
Surfing the internet withoutproper antivirus security will allow unknown viruses to infect your computer Besideshat, viruses can also replicate themselves When one of your files is infected, you shouldcheck and scan all of your other drives You may discover that the virus had alreadyreplicated itself to some of your foldersAnyhow, all computer viruses are manmade A simple virus that can make a copyof itself over and over again is relatively easy to produce Even such a simple virusdangerous because it will quickly use all available memory and bring the system to a haltart from that, an even more dangerous type of virus is one capable of transmittinself across networks and bypassing security systems When one computer is infectedthe rest of the computers in the network will have a very high chance of getti
pdate "feature that you can schedule to automatically update your software anycomputer is on, even if you're not home If a particularly notorious virus has beenleased recently, update it daily for about a week It may be a pain, but it's worth itAntivirus softwaresMcAfeeMcAfee's advanced retail desktop solutions include premier anti-virus, securencryption, and desktop optimization software, McAfee's managed Web securityservices employ a patented system and process of delivering software through anInternet browser to provide these services to users online through its Webhttp://us
mcafeecom,oneofthelargestpaidsubscriptionsitesontheInternetwith over two million active paid subscriberMc Afee gives you two ways to protect your PC against nasty viruses and wormse Sasser, Mydoom and Lovsan/MSBlaster You can purchase Mc AfeVirusScan for real-time virus protection or McAfee Web Essentials for 2-in-1protection from viruses and hackers
virus scanFreeTMcAfee virusScanMcAfee Web EssentialsProtects your Pc from over 87,000 virusesans and hackersDetects spyware and adware protecting loss Detects and quarantines spywareof data and privacyweb dialers
adware and moreScans e-mail downloads CD-ROMsFree updates and upgrades duringInstant Message attachmentour subscriptWormStopper detects and stops massmailing wormsects and attempts to clean malicious codeFree updates and upgrades during yoursubscriptio
2 Norton AntivirusAntivirusSymantec's Norton AntivirusTM 2005Symantec's Norton AntiVirus 2005 is the latest version and it is the world,s mosttrusted antivirus solution It removes viruses, worms, and Trojan horses automaticallywithout interrupting your work New Norton M Internet Worm Protection blockscertain more sophisticated worms(such as Blaster and Sasser) before they enter yourcomputer Norton Anti V irus can also detect spyware and other non-virus threatsNortonTM Internet Worm Protection stops certain damaging Internet worms at theirattempted point of entry
Quick Scan tool automatically searches for and removesviruses whenever new virus protection updates are downloaded Prelnstall Scanquickly detects and removes infections that can interfere with installing and launchingorton Anti Virus It will scans and cleans both incoming and outgoing emaimessages It can blocks viruses in instant message attachments It will detect spywareand certain non-virus threats such as adware and keystroke logging programs Onother hand, it will download new virus protection updates automatically to protect
Email precautionsLike the telephone, email is one of the quickest and most convenient forms ofcommunication today We send them through the offieour children, and toclients We use it because it is quick and easy We have electronic address books insteadof little black books Email frauds commit their crimes in a way similar to con artistcommit their crimes over the telephone Creators of email viruses prey on you byclaiming to be from somebody that theyre not
The good news is, you really don' t have tobe a victim, if you're armed with the right informationhe easiest way to prevent a virus is to not engage in the activity that causesto spread If you're not willing or able to give up your email entirely, there are a fewidelines to make your email use a lot safer Don't download files from strangers If yousimply must read the attachment, however, download it to a floppy disk to be on the safeside, and then scan it with your anti-virus software This is the safest way to handledownloads because the file is not accessible from a network drive or your hard diskyou get a virus warning sent to you, make sure to check your software provider's websiteto make sure it's accurate
Identifying potential viruses in E-mail attachments/henever you receive an attachment in MS Outlook /Outlook Express therely a picture of a paper clip, Single clicking the papels thatfiles attached Notice that the attachment above appears to be a Word document becauseof the doc extent appear to be a typical Ms WordThe typical Ms Word icon is a picture of a blue W, as shown below(at left)osoftWordBatch FileDocumentIcon batGood Attachment" vs"BaNotice how the attached file in the e-mail above is called "The pillarbanguet wine docbut has a different icon(depicted above right ) In this case, the file is really a batch filewhich contains potentially dangerous commands The entire file name of the above fileis The pillarbanquet wine doc
baany commands thatareained within would be executed, including deleting all your files orreformatting your hard drive Depending on how your computer is configured, it maynot be set to show file extensions or extensions of registered files or system files Thismeans that you may never see certain types of extensions(bat, com, exe, pif, etc
Good FilesTypically, "good"attachments will have a picture of their associated program, such asMS Word Excel Acrobat Reader etc回圖四MicrosoftMicrosoftWord Icon doc Excel Icon xls Icon pdfEven"good"files can contain viruses
There are some macro viruses that are embeddedMS Office documents(Word, Excel, etc ) The best bet is to always make sure thatyour virus definitions are up-tBad filesThere are a number of files that can cause problems Anything that ends in bat, com,exe, scr, vbs, Ink, pif can cause external commands to be run Below is a sample ofwhat the icons nlook likeBatch FileExecutable Script Filepif)
Knowledge on virus preventionDo not open any files attached to an email from an unknown, suspicious ortrustworthynot open any files attached to an email unless you know what it is, even if itdear friendthemselves and spread through email Better be safe than sorry and confirm that theyreally sentDo not open any files attached to an emailsubject lineunexpected If the need to do so is there always save the file to your hard drive beforeDelete chain emails and junk email Do not forward or reply to any to them Thesetypes of email are considered spam, which is unsolicited, intrusive mail that clogs upe networkDo not download any files from strangersExercise caution when downloading files from the Internet ensure that the source is alegitimate and reputable one
Verify that an anti-virus program checks the files on thedownload site If you're uncertain, dont download the file at all or download the fileto a floppy and test it with your own anti-virus softwareUpdate your anti-virus software regularly Over 500 viruses are discovered eachmonth, so you'll want to be protected There updates should be at the least theproducts virus signature files You may also need to update the products scanninengineBack up your files on a regular basis
Even though all the computer viruses are manmade, not all of them are dangViruses, as purely replicating entities, will not harm your system as long as they arecoded properly Any system damaely replicatingbecause of bugs in the code that conflict with the system s configuration In other words,a well-written virus that only contains code to inferms will not damageystem Your programs will contain the virus, but no other harm is doneWHAT IS ANTIVIRUS SECURITYAntivirus securities are the measurements of prevention that protects a computerfrom the infection of viruses out there in the huge computing world a computer has tobe armed to protect itself from the attacks of viruses
Antivirus security comes in manydifferent forms There are antivirus programs which can help detect and prevent virusesfrom coming in Antivirus programs such as Mc Afee and Norton Antivirus are quitepopular in the computing world for their abilities to protect a computer from viruInstalling antivirus software into a new computer is very important, especiausersBesides that, personal know ledge on computer viruses is important too Anyonehas a computer should check out the latest news about viruses and antivirus securityprograms Lets take a look at the many different types of virus in the next section of thiKnow more about Security System to visit on ESET Key
Different Types of virusesComputer virus is a program which reproduces itself Viruses has manydifferent ways to attack to the computer such as create copies of itself, damage or corruptchange data and degrease the performance of the computer system Computer viruses canbe categorized with few designations which are File infector viruses, Boot Sector virusesMaster boot record vi
ruses, Multi-partite viruses, macro viruses, Trojan viruses andWorms Below is the list to introduce different type of viruses and how they can beFile Infector Viruses- it infects program files which contxecutablescode like eXe and com files Beside that it can infect other files when an infectedfrom flhard drive, or from the network Some file infectors are memoryresident It means that the virus will stay in memory to infect other filesFor example, acompanion virus might create a hidden PGP COM file so that when the PGP command isexecuted the fake pgP com runs first The com file invokes its virus code beforegoing on to start the real PgPeXe fileBoot Sector Viruses-bring infect to the boot record on hard drive, floppydisk, and Disk drive All floppy disks and hard disks contain a small program in the bootecord that is run when computer starts The viruses attach themselves to this part of thedisk and action when the user attempts to start up from the infected disk, boot sectviruses have become less common as floppy disk have become rarer Examples of bosector viruses are Form, Disk Killer, Michelangelo, and Stoned
Master boot record viruses- it is very similar with boot sector virusesexcept that the viruses infect the mBr which is Master Boot Record) The differencebetween these two virus types is where the viral code is located master boot recordinfectors normally save a legitimate copy of the master boot record in a differentcation Examples of master bod infectors are NyB antiExe and UnashamedMulti-Partite Viruses- it shares some characteristics of boot sector viruses andfile viruses These mean that they can infect com and eXe files and the boot sectorof the computer's hard drive It is very difficulty to repair If the boot area is cleanedbut the files are not the boot area will be infected If the virus is not removed from theboot area, any files that you have cleaned will be infected
Examples of multi-partiteviruses include One Half, Emperor, Anthrax and TequilaMacro Viruses-compare with the rest, the newest type of virus and tendbe a least damages the first macro virus, written in microsoft s word macroanguage, was discovered in August, 1995 Currently, thousands of macro viruses areknown to exist and include viruses written in the macro language of Microsoft s ExceWord and AmiPro applications These types of viruses infect data files They are themost common and have cost corporations the most money and time trying to repairMacro viruses can be spread to any machine that runs the application the virus waswritten in Examples of macro viruses include w97M Melissa, WM NiceDay and97M Groo
Trojan viruses- are defined as a"malicious", security-breaking program Itpread when people are lured into opening a program because they think it comes from aitimate source But actually conceals something bad Trojans can be spread in theguise of literally anything people find desirable, such as a free game, movie, song, etcVictims typically downloaded thefrom a www or ftp archive got itto-peer file exchange using IRC/instant messaging/ Kazaa etc, or just carelessly openedsome email attachment Trojans usually do their damage silently Example for somenames include: " dmsetup exe"and"LOVE-LETTER-FOR-YOUTXT vbsBack Orifice is one of the new Trojan viruses that provides a backdoor into ourcomputer when active and connected to the InternetWorms- A worm is a special type of virus that can replicate it and use memorbut cannot attach it to other programs
Unlike viruses, worms require the spreading oan infected host file altgh worms generally exist inside of other file like WordExcel documents, Usua lly the wormelease a document that already has the wormmacro inside the document The entire document will pass in to a computer to anothercomputer, and the whole document can be considered have worms inside One of theexamples for worms viruses is Pretty Park Worm Melissaviruses with combination Word macro virus and E-mail worms a conclusion, computer viruses are getting more popular in nowadays Theycan spread and hide anyway in the computer file without our knowing and against ourwishes A simple virus can make a thousand copies stay in the computer file Adangerous virus is capable to transmit themselves through the network and even break
the security system if without a well protection for the computer systems This is veryimportant for people to know about differences of viruses and how did a computer to getinfected by those viruses The second thing for prevent the problem ofemputing system This is very important that for every people must have a good antder to prevent the problems occurredHOW VIRUSES ARE SPREADe there are many types of virus in the computing world, there are also manyways how viruses are spread viruses come in different forms and their ways of attacksare all different Sometimes, you wont even know that a virus had already infected volcomputer They have the ability to attack your computer without notice but of course,your individual actions are also partly responsible for the attacks of viruses
Lets look ate different ways of how viruses are spreadEmail Attachmentsce the existence of the internet email had become a very common form ofcommunication between many users In fact email had become one of the cheapest andmost convenient methods of communication Sadly, viruses can be spread throughemails Viruses may disguise themselves as pictures, screensavers, programsrddocuments and many other file types These viruses may come in forms of attachmentsent to you by unknown users Electronic greeting cards, links to certain websites andother techniques may be used by virus programmers to infect your computer with thetended virus when you click or open the link
File Sharingn a network, file sharing is a really good way of sharingresources ofnd usefulfibetween the users of the computers on the network But sadly, many viruses have thes through open network shares When you copy somethifrom a network, you have a slight chance of getting infected by a virus Any files orfolders that are obtained through a network must be scanned by antivirus programs beforehemDownloading Files or SoftwareMany files or software can be obtained for free through the Internet but beware,ot all of these files are safe, There may be viruses hidden among these files
If the fileyou are downloading, or the computer you are downloading from it is infected with aS, chances are pretty high that your computer might also become infected with thevirus Try to avoid downloading files from another computer unless you have verifiedith the computers owner that proper antivirus software is installed and up-to-dateInstant MessaginInstant messaging programs are very famous among computer users Programse ICQ, IRC, MSN Messenger, Yahoo Messenger and AOL messenger are verypopular In reality, instant messaging programs are not dangerous in spreading virusesThe biggest risk here comes from accepting files from other users on the networkStrangers whom you just met from these instant messaging programs should not be
trustedandcept any unknownfrom them virusesidden among the files you received and it will activate itself when you open the fileFloppy disksFloppy disks are handy items as it is convenient and useful to transfer filesHowever, it is also very susceptible to viruses a clean floppy disk can become infecteden it is used in a computer with a virus infection If an infected floppy disk is used in aclean computer, that computer can also become infected with the virus When you wantto copy some files to or from a computer, make sure that the computer is safe fromviruses
Thisransfer files from a floppy disk into your owncomputer But now, floppy disks are seldom used by computer users It is replaced by thehandy USB key or flash memory as they call itWebsitesNowadays, there are millions and millions of websites on the World wide WebInformation about nearly everything under the sun can be found through the many webpages in the Internet Sadly, certain viruses are known to infect web servers, and intheory, if you visit a website that is hosted on an infected server, your computer couldbecome infected with the virus There is not much prevention that you can do aboway these types of viruses spread However, this infection method is very rare
ter virus preventithis modern century no matter what your circumstances were whether youwere annoyed or infected, panicked or fascinated, the virus took over the world'scomputers by storm There are many computers in this world attacked by viruses Emailystems were blocked, files disappeared, and users were left puzzled about the fact thahey got and somehow they had been fooled again The clever disguise of the virus tookmany people by surprise The worst thing is people have no idea when the virus willattack their computers What went wrong? With all the talk and hype about virusprotection, how could we have been fooled again?The best way to treat a cold or a virus is to avoid catching it in the first place Thesame goes for your computer You can help to prevent viruses from infecting yourcomputer or spreading to other computers
Here are some ways you can help to inoculateAnti-Virus software is a necessity nowadays If you dont have it, now is the besttime to shop for it! In stead of the recent virus attacks, many of anti-virus companies aregiving away free 30-day-trials You have to download the antivirus before your computercatches a virus There are two famous antivirus software mcafee s viruNorton Antivirus you can shop on the internet Be sure that the operating system you'reusing, such as Windows 98, is compatible with the program you choose Once you getyour software, make sure you update it at least once a week, and that you have it set toscan for viruses when your computer boots up Most of these programs have an auto