ComboFix
Once you download ComboFix, you can execute the program to be guided through the wizard to give you a steb-by-step instruction on how to remove the destructive malware that has rendered your computer useless. There have been reports on ComboFix forums that show destructive behavior has occured, so be cautious and only use this program if you are a trained professional and this is the last resort to recover the computer.
ComboFix has gained in popularity because the software is very effective in removing several infections. ComboFix is one of the few freeware programs that accomplish this goal. Other programs charge a subscription fee and we are thankful to sUBs for writing this software and making it free for use.

http://www.combofixdownload.com/