Hello all! As background: I have a 64 bit Vista Ultimate rig running Virtual PC 2007 (SP1), with a Vista 32 bit VPC set with Shared Networking (NAT) and with Undo disk turned on (i.e. you can dispose of changes after each session). The host machine runs Windows Live OneCare (firewall, AV/AS, etc.), and I run as an Administrator on this machine, but with UAC turned on. The virtual PC is running NOD32 2.7, and I run as a Standard User on this instance. I fully patch Windows when updates come out, and update NOD32 before going on the internet with this virtual PC. How great is the risk of the host becoming infected with a virus from the virtual PC in such a configuration? I know its theoretically possible, but how realistic? Thanks in advance!