Please Help! C-Drive Disapeared out of My Computer

I need some help please. I double clicked on my flash disk and then some ‘‘thing’’ installed on my PC. Straight after that happened my C-Drive went missing out of My Computer, I can also not access my task manager. Please help!!

I suggest:

  1. Disable System Restore and reenable it after step 3.
  2. Clean your temporary files.
  3. Schedule a boot time scanning with avast with archive scanning turned on.
  4. Use SUPERantispyware and/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 than.
  5. Test your machine with anti-rootkit applications. I suggest avast! antirootkit or Trend Micro RootkitBuster.
  6. Make a HijackThis log to post here or, better, submit the RunScanner log to to on-line analysis.
  7. Immunize your system with SpywareBlaster or Windows Advanced Care.
  8. Check if you have insecure applications with Secunia Software Inspector.