Viruses are spread via floppy disks and networks, dedicated to reproducing themselves and getting into as many computers as possible. They’re created by programmers who on some level want to show off. Some are trying to settle some score with the world, but most virus writers don’t particularly care who gets hurt.
A pure-text file can’t contain a virus. Most viruses infect programs that you run on your computer. But newer ones, called macroviruses, are especially scary because they use programming languages built into some of the latest applications such as word processors or spreadsheets. If you get an infected document via e-mail and merely open it, the virus goes to work.
Truly malignant viruses will intentionally erase your hard drive so thoroughly that your computer won’t even start again without a trip to the shop. But many are more subtle: All you know is that a word-processor file disappeared and you can’t find it anywhere, or a spreadsheet command doesn’t seem to work the way it should, or a couple of keys on your keyboard seem to be stuck or won’t type what they should.
How can you avoid such pain? Practice safe computing.
First, keep backup copies of your data files. This will protect you from the worst effects of so many computing disasters, not just viruses, that it should be the first thing anyone learns to do on a computer.
Second, don’t swap floppies with just anyone. This helps only a little because the cleanest, healthiest-looking floppy from the nicest person can still have the virus. Even programs from software companies can be infected.
Third, don’t download files from the Internet from just any site. Again, like the floppy story, you’re less likely to get a virus tag-along from a well-known, commercial Web or FTP (File Transfer Protocol) site, because those folks normally watch out for and eradicate viruses. But even they make mistakes.
Fourth, get and use an anti-virus program. And if you want the best protection, keep that program up to date.
Anti-virus programs are normally found in the utility section of your software store or catalog. They can find and then erase most computer viruses. They do this by watching for two things: known virus “signatures” (recognizable shapes of viruses on disk or in memory) and known virus activities (unauthorized attempts to erase or change things on disk). You can employ them periodically in complete searches of your disks, finding and erasing all viruses on your hard drive and floppies. Keep in mind that the best virus-finders are not necessarily the best virus-killers.
Once floppies are clean, you can switch their “read/write” sliders to the “read-only” position, and then no new viruses can get on. CD-ROMs could come from the factory with a virus but can’t acquire one from your computer because they are always “read-only”–no new programs can be stored onto them.
You can also employ anti-virus programs as constant monitors. Like metal detectors scanning people entering an airport, anti-virus monitors can detect any viruses trying to enter your computer.
An anti-virus program should offer immediate scanning and permanent monitoring, and the part that stays in memory to monitor should be as small as possible. It should recognize and eliminate as many viruses as possible. These include macroviruses, boot-sector viruses that get right to the foundation of your disks; multipartite, which include regular and boot-sector activity; and polymorphic, which change shape to avoid being noticed by any one signature.
If the anti-virus program also recognizes Trojan Horses–programs that purport to be handy utilities, but are actually predators in disguise–that’s a plus.
It should scan normal disk files, compressed files, programs in memory and files you’re downloading. It should scan them immediately if they’re coming from outside your computer, such as when you insert a new floppy disk.
So which anti-virus program is best? That depends on your computer.
– Macintosh programs. Mac owners should head straight for “Disinfectant” (http://charlotte.acns.nwu.edu/jln/progs.html ).It is small, fast, solid and free. Creator John Norstad releases new free versions of Disinfectant as new viruses warrant.
McAfee’s “VirusScan 2.0” (800-332-9966, http://www.mcafee.com) is a $45 (street price) commercial version of Disinfectant. It’s easy to use, but unable to scan compressed files. The $49 fee for a year of signature updates is steep, too, but at least there’s a free, 30-day demonstration version on-line. To get the real thing you’ll pay around $45.
You could also turn to Symantec Anti-Virus for Macintosh (800-441-7234, http://www.symantec.com). List price is $85, street more like $70, and signature updates are free for a year.
Datawatch’s “Virex 5.7” (800-847-3982, http://www.datawatch.com) is impressively fast but too hard to use for my tastes. The full version costs $70, plus $30 more for a year of updates, and there’s no downloadable trial or demo.
– PC packages. There’s no Disinfectant for PCs, which is both a shame and understandable, with so many more viruses attacking PCs. But too few of the PC virus products are even available in trial or demo versions.
My favorite PC anti-virus program is McAfee’s “VirusScan.” It puts DOS, Windows 3.x, Windows 95, Windows NT and OS/2 versions in the same box. They’re good at finding and great at killing viruses. The relatively low price of $45 is offset by a high update fee, but that fee gets you 24-hour tech support.
Another top program is “Norton AntiVirus” (800-441-7234, http://www.symantec.com), $70 for both software and updates. Check out the trial versions–2.0 for Windows 95 or 3.0 for Windows 3.x and DOS.
Dr. Solomon’s Anti-Virus Toolkit (888-377-6566, http://www.drsolomon.com) and F-Prot Professional (800-423-9147, http://www.commandcom.com) are my least favorites in ease of use, though both are said to be very powerful.
Also consider: IBM’s AntiVirus 2.5 (800-742-2493, http://www.av.ibm.com) and ThunderByte’s AntiVirus Utilities (800-667-8228, http://www.thunderbyte.com).
Several Web sites boast solid information. Symantec’s “AntiVirus Research Center” (http://www.symantec.com/avcenter) and IBM’s anti-virus on-line magazine (http://www.av.ibm.com) offer real-life stories, technical details and even “hype alerts” about viruses that are more hoax than hex.
