what virus software do you have running? have you ran a scan, Run in safemode and run a full system scan.
Also running a repair on XP / 2000 / vista will not remove a virus as this only repairs the files windows installs itself, and the virus is usally a file on its own which then in turn infects other files.
If you do not have a virus software id suggest you get some soon, NOD32 being my choice, you can also get a free online scan which may take some time.
If possible always do this full system scan in safe mode as this allows alot more files and folders to be scanned.
http://bitdefender.com is a good one.