ComboFix usage, Questions, Help? - Look here http://www.bleepingcomputer.com/forums/topic273628.html
ComboFix is an Anti-Malware tool used by advanced malware technicians specifically trained in its use. I used ComboFix on a 64-bit system and cannot get it to work?
Please DO NOT USE COMBOFIX on your own without supervision!!!
: Combofix currently only works with Windows 2000/XP/Vista/Windows 7 (32-bit
Due to the architecture in 64-bit Windows and the fact that 64-bit drivers need to be digitally signed, rootkits are not seen as often in 64-bit machines so they are less prone to that type of infection. As such, it is very unlikely that there will be a 64-bit version of CF since that OS is more secure than a 32-bit system. Note
: Although ComboFix will work on Windows 7, it is not
officially supported yet so if it is run you will receive a warning message
that it is a beta version meant for compatibility testing.