Do you know if you have a virus on your computer?
Try housecall, it is free to use and offers great information. HouseCall can only detect viruses already on your system at the time you run your scan. Housecall has detected some viruses that Norton and McAfee missed and cleaned or repair some they could only quarantine. This is a great tool!

http://housecall.antivirus.com/pc_housecall/

Protecting your system against computer viruses typically requires two steps. First a scan of your existing system (which HouseCall does), then a continuous scan of all file activity (or real-time protection) which is done through the installation of a good antivirus software.

To protect your computer from viruses
You will need to purchase an Anti-Virus Software.
Some great software is
Norton Anti-Virus 2002, which you can find at http://www.symantec.com
or check out Trend-Micro http://www.antivirus.com/pc-cillin/

If you open an infected Word document attached to a new email or insert an infected diskette into your computer, HouseCall won’t detect it.

What is a virus?
http://www.antivirus.com/pc-cillin/vinfo/vprimer.htm

Virus Info Center
http://www.antivirus.com/pc-cillin/vinfo/default.asp

Comparison Chart
http://housecall.antivirus.com/pc_housecall/comparison_pcc.htm