Trojan.Zeroaccess!inf4

The activity message in NIS says

 

services.exe (Trojan.Zeroaccess!inf4) detected by Virus scanner and Auto-Protect

 

Apparently Quads is the guy to go to for help with this so if you have the time I'd really appreciate some help

 

Thanks in advance

 

Auto-Protect is popping up every few minutes telling me that it has blocked a trojan and I'm on Windows 7 Home Premium - 64 bit if that helps at all