Vista Service Pack 1 disables Parallels

I have been using Vista with parallels. Everything was working fine until Vista loaded service pack 1. Now when I reboot it gets stuck loading drivers and won't actually boot into Vista at all. Have tried safe mode and all the other options but the same thing happens. Have tried booting from the CD but again, the same problem occurs...
I cant now access a computer I've been working in for months!
Can someone help?

 

I had the same problem. I had to repair the windows installation, but the computer wouldnt recognize my external usb super drive. I uninstalled parallels which doesnt delete the virtual machine (windows) that you have created. After reinstalling Parallels, i then repaired windows and windows boots again. I am waiting to see if there is a fix for this as I am running software which needs .Net 4 which won't install until i have the service pack installed....which wont currently run on Virtual Windows Vista !

thx

Peter