If a virus is replicant (coming and coming again), you could follow the general cleaning procedure:
1. Clean your temporary files. You can use
CleanUp or
CCleaner for that.
2. Schedule a boot time scanning with avast. Start avast! > Right click the skin > Schedule a boot-time scanning. Select for scanning archives. Boot. Other option is scanning in
SafeMode (repeatedly press F8 while booting).
If avast does not detect it, you can try
DrWeb CureIT! instead.
3. It will be good if you download, install, update and run
SUPERantispyware,
MBAM or
SpywareTerminator.
If any infection is detected, better and safer is send the file to Quarantine than to simple delete them.
About legit antispyware applications or the bad ones see
here.
4. If you still detecting any strange behavior or even you're sure you're not clean, maybe it will be good to test your machine with
anti-rootkit applications. I suggest
avast! antirootkit or
Trend Micro RootkitBuster for XP/Vista. For XP only:
Panda.
5. Also, if you still detecting strange behaviors or you want to be sure you're clean, maybe making a
HijackThis log to post here or
this analysis site. Or even submit the
RunScanner log to to on-line analysis.
6. After you're clean, disable System Restore on Windows
ME,
XP or
Vista. System Restore is not available in Windows 9x and 2k. After disabling you can enable it again.
7. Use the immunization of
SpywareBlaster.
8. Finally, when you're clean, check for insecure applications with
Secunia Software Inspector to update insecure applications and avoid reinfection.