Format the drive. My computer may have a virus. The basic steps to removing a virus is to power the infected system down, boot up from a clean diskette, then check the system for a virus. Power your system off. Don't just hit reset but completely shut it down.
Some viruses can remain active during a warm boot.
This diskette should have anti-virus software on it such as McAffee's or Norton's antivirus programs. Most of the anti-virus software out there will allow you to make an emergency boot diskette. If you've been smart enough to get one of these programs then pat yourself on the back. The emergency boot diskette will have the necessary files to boot up and check your disks for viruses and clean them if necessary. This is the sector that contains the information necessary for your operating system to load.