The problem is not just with VM. After installing the SP1 on my macbook pro 15.4" running vista ultimate via bootcamp, my system seemed to be running properly for several day until I accidently reset my bluetooth mouse. I found out that I was not able to pair the mouse with the computer using bluetooth anymore. It kept complaining invalid driver and could not find the driver no matter what I tried. To my madness, insertion of any usb device would trigger driver installation and the invalid driver error. I resolved the problem by uninstalling the SP1. Everything is back to normal. I have Norton antivirus installed on my system. I am suppecting that it may be conflicting with the vista SP1. However, I did uninstall NAV first before resolving to uninstall the whole freaking SP1, and it did not help. To my dismay, there was a mini network driver showing up in the device manager with a warning question mark that would not go away. I searched the net and confirmed it was left behind by SP1, and found a window command to get rid of it. Unbelievable!!!