I have a dual core 3.5GHz computer that I was running WinXP until last December when I upgraded it to Win7 x64. In XP I installed VPC 2007 SP1 and created a Win98SE, WinME, WinXP (for when I went to Win7) and a Vista VM so I could test my apps in those different environments. I would periodically do Microsoft updates on the XP and Vista VM's as well. December I've wiped out XP and installed Win7 then installed VPC 2007 SP1 x64 and those VM's all run fine, except doing microsoft updates on the Vista VM, I can do MS updates on the XP VM but not the Vista one, anyone have any idea as to why?