After applying the recent updates for Parallels and the commensurate Tools, I now cannot use the Bootcamp VM that I usually rely upon. Additionally, there were some Window's updates that occurred (when isn't there?) yet I don't know if those affect the situation. The system boots fine to the Windows login screen. After supplying username and password, the 'Welcome' message is displayed. After a few moments (30 or so seconds), I'm presented with a blank screen the color of my desktop background. However, there are no toolbars, no icons, etc. Moreover, sending CTRL-ALT-DELETE shows the appropriate menu, however, starting task manager apparently does nothing. Normally, I figure things out myself. However this has me stumped since its not the 'Black Screen' issue. The desktop appears normal when running in 'safe mode' after a 'reset' from the virtual machine menu. I've given it 4GB of RAM and 1GB of Video memory. Argh...
Try to recreate the boot camp based VM . As all your data is stored in the boot camp - you won't have to reinstall anything