Wroking with a client that got the FBI Warning Virus, telling them to pay $300 or the government to be after them or something.
To get rid of it:
Start in safe mode.
Get them Hitman Pro and run it in safe mode.
Delete the malware it finds
Reboot in normal windows and it should all you to get access w/e the FBI warning popping up.
Run Hitman Pro again and TDSS killer which you can get from the Kaspersky website.
TDSS killer is anti-rootkit so if it is hiding in there it should find it.
Have to run TDSS killer in normal windows mode for the root-kits to be active.