Preventing Viruses

In any event, it’s far better to prevent a virus infection on your computer rather than attempt to deal with it afterwards.  That’s because a virus can cause irreversible damage if left unchecked for a long period of time.  Granted, a virus will never physically damage any of your hardware, but a serious case of infection could require the user to reformat his or her hard drive and start from scratch.  So basically you want to make sure you never get a virus to begin with, and there are various ways to work toward this goal.  Of course, even the best virus prevention may not stop an infection.  A simple lapse in judgment could lead to the user running malicious code without even thinking about it.

Basic virus prevention

Since a computer virus requires user input at some point to begin an infection, your most basic defense against viruses is to not run programs that you’re not sure about.  You can run programs off CD-ROMs manufactured and purchased from software developers.  There’s no real risk of an infected program if it’s coming straight from the developer.  The real trouble comes from downloaded programs since most people don’t even use floppy disks anymore.  Always keep track of whether a site appears to be a legitimate source.  If you’re downloading stuff off a peer-to-peer file-sharing network, for instance, there are no controls present against infected files.  The same holds true for pirated software applications and games.  If you do have to download a program off a source that you’re unsure about, you should always run a virus scan on the downloaded files to check for viruses.  Though they’re not as common as worms anymore, you should always check.

Basic worm protection

Worms, on the other hand, are an entirely different animal.  Depending on the complexity of a worm, there may be no way to prevent its infection on your system.  The most common way of receiving a worm is through spam or from another infected computer’s e-mail.  They usually come in the form of an attachment or file that appears to be something like a screensaver or another useful program.  If you do happen to run this attachment, you’ll get nailed with the worm and it may automatically start sending itself to everyone on your contact list.  Most modern e-mail programs have a separate directory reserved for attachments, and may even scan attachments for malicious code.  Don’t rely solely in built-in security, as major programs like Microsoft Outlook have known vulnerabilities.  Instead, never run an attachment for any reason unless you’re expecting one from a friend or colleague.  Even then, you should always scan your attachment directory for viruses and worms.

Real-time protection

All virus scanners offer a real-time component that actively scans your computer along with the websites and incoming files associated with Internet usage.  Any time a new file is created on your system, it gets scanned.  These are perfect for those who are concerned about virus or worm infection.  However, I find that these programs interfere with daily use (you get interrupted a lot to be notified of changes to your system and scheduled scans).  Furthermore, these active scanners sap your system resources and also keep a direct line open to the definitions server.  While this is good in that your virus definitions will be up to date, the less open connections to the Internet, the better.  So unless you don’t feel you are advanced enough to actively scan things on your own and be careful, there’s no need for real-time protection.