Antivirus Software
< return to Safety Zone >
< print this >
WHAT IS A COMPUTER VIRUS?
DEFINITION: A computer virus is a piece of programmed software that has been maliciously designed to cause harm or disruption to the functioning of your computer or its files.
HOW DO YOU "CATCH" A VIRUS?
A computer virus can be planted in a file that you unknowingly receive in email, in a download or on a disk. Modern virus programmers are fiendishly clever, and often transmit the virus-infected file in a harmless or innocent-appearing guise.
Viruses embedded in email attachments are probably the most common, and they often are passed on, unwittingly, by people whose email address is familiar to you, or even can be made to automatically infect an individual's email system and automatically pass on the virus to everybody in that individual's email address book, without them having any idea that this is taking place.
Files downloaded from untrusted Web sites on the Internet, infected files inadvertently copied to a floppy disk or CD and passed on, or files sent by way of an instant messenger service can be other ways your computer can become infected.
WHAT CAN YOU DO TO PREVENT OR REPAIR A VIRUS INFECTION?
- Buy and install a reputable antivirus software program, and keep it updated. Critical: Your antivirus software can be worthless if you fail to regularly update its definitions or virus lists! We recommend that you subscribe to automatic update services from your software's publisher, or manually download updates yourself no less frequently than every few days, if not every day.
- Never open email attachments from unknown sources (and be very wary of any that still may come from trusted sources).
- Do not respond to "spam" email (i.e., unsolicited email from unknown sources).
- Consider online filtering services, such as EONI's optional email filtering system, as a "first line" of defense. (Be aware that no antivirus solution is perfect; each uses different algorithms and approaches, it can take time to devise antidotes to new viruses, etc.)
- Do not open files on a floppy disk or non-trusted CD without first performing a virus scan on the disk.
- If you suspect you have a virus, but are not running an antivirus program, you can get help by visiting the Web sites of the leading antivirus software publishers, such as Symantec, McAfee, Sophos, etc. In some cases, you may be able to download a repair tool for a specific virus that you have identified from these sites. However -- visit these Web sites with a "clean" computer.
- If you suspect you have a virus, take corrective action such as described above before you run your email software or use your computer. Do NOT run data backups, make copies to external disks, connect to other workstations or users if you are on a network, or send email if you believe your computer is virus-infected.
- If your computer becomes severely virus-infected, you may have to reformat your computer's hard disk and reinstall the operating systems and its programs from scratch. Seek the help of a professional if in doubt.
- Beware of antivirus hoaxes. Sometimes people naively pass along messages warning you to delete particular files from your computer when those files are in fact harmless and may even be crucial to the proper operation of your system.
- Above all, exercise reasonable judgment and keep yourself informed by regularly updating your own knowledge of virus threats and virus hoaxes. Don't take action if you are uncertain based only on unsolicited, unknown sources or even on that of well-meaning but uninformed nonprofessionals. Visit the "name brand" antivirus publishers' Web sites or sites such as the US Department of Energy's Cyber Incident Response Capability (CIRC) site for credible reports on threats and hoaxes.
WARNING: It is not enough to rely solely on a single type of antivirus protection. For example, EONI offers email filtering services, run through its servers, that screen incoming mail according to your configuration settings, but you would still need antivirus software on your own computer to deal with viruses that may arrive if you also receive mail under any non-EONI email addresses, or that could be infected in downloads or other files that you copy onto your computer. ( For more information on EONI email and Internet content filtering services, see http://home2.eoni.com/servicesFiltering.cfm )
