Rootkit - MALWARE TYPE

Hi fellows from Avast! I’ve been receiving this kind of message from my Avast! I’d like to know what I can do to clear up my computer. It’s about rootkit. Please, help me to find the best solution for this worm.
Many thanks,

Scipione.

C:\DOCUME~1\UserName\CONFIG~1\Temp\08580.sys - FILE NAME
Win32:Rootkit-gen [Rtk] - MALWARE NAME
Rootkit - MALWARE TYPE
090220-0, 20/02/2009 - VPS VERSION

AVAST! WARNING
malware was found!
There is no reason to panic, though. Ty to follow the given advice and links

Send the file to Chest and follow the general cleaning procedure:

  1. Clean your temporary files.
  2. Schedule a boot time scanning with avast with archive scanning turned on. If avast does not detect it, you can try DrWeb CureIT! instead.
  3. Use SUPERantispyware, MBAM or Spyware Terminator to scan for spywares and trojans. If any infection is detected, better and safer is send the file to Quarantine than to simple delete them.
  4. Test your machine with anti-rootkit applications. I suggest avast! antirootkit or Trend Micro RootkitBuster.
  5. Make a HijackThis log to post here or this analysis site. Or even submit the RunScanner log to to on-line analysis.
  6. Disable System Restore and then reenable it again.
  7. Immunize your system with SpywareBlaster.
  8. Check if you have insecure applications with Secunia Software Inspector.