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Although there are thousands of computer viruses known to researchers, the vast majority are locked away in computer labs. Of the 500 or so viruses that exist "in the wild," most are relatively harmless--they may eat up a bit of extra memory, but they probably won't overwrite your hard drive or destroy your work files. But you shouldn't take any chances. Follow these simple steps, and you'll be on your way to carefree computing:
1. get some antivirus software No antivirus software is perfect, and false alarms can be almost as annoying as viruses themselves. But no computer in today's highly networked, disk-sharing world should be without antivirus software. Be sure to update it frequently--new viruses appear all the time.
2. watch those disks In general, you should be very wary about inserting floppy disks from unknown sources into your disk drive, especially if the disks have been shared by several other people. But sometimes you have no choice. In those cases, the second thing you should do (after putting the disk in your drive) is to scan the disk with antivirus software. Scan every file on the disk, not just the program files. Do this even for shrink-wrapped software. Likewise, when you give a floppy to somebody else, always write-protect it. That way, a virus on someone else's machine won't pass over to your disk (unless the person removes the write-protection to make changes--then any problems are their fault). CD-ROMs are less risky, but scan them the first time you use them anyway. The Concept virus was found on CD-ROMs for the Windows 95 Software Compatibility Test and Windows 95 Support Tools for Windows NT.
3. download with care Many computer users believe that downloaded files are the most common source of viruses. Nothing could be further from the truth: the vast majority of viruses travel through shared disks or files on a network. Still, you cannot be too careful, especially if you're using illegal or "underground" software like AOL4Free (which, in many cases, is actually a wicked Trojan horse). To be safe, download all files into a special folder on your hard drive. Then be sure to scan those files before you open them.
4. scan attachments before reading them While it is impossible to get a virus simply by reading an email message, it is very possible to get one through an attachment. Some email programs will automatically open certain attachments with the appropriate program. This is a nice touch and can make reading attachments a bit quicker, but it's also a potential virus nightmare. Disable this function in your email program, then scan any attachments you receive before you open them.
5. save shared files in RTF or ASCII format If you want to share data on a network server, and you want your computing experience to remain perfectly virus-free, save all files in RTF or ASCII format. Neither file format saves macros and formatting information, so this step will help prevent macro viruses.
6. back up everything Back up your work files and system configuration files regularly. Store these backups in a safe place, separate from your hard drive. That way, if your system becomes infected by a virus, you'll have copies to fall back on.