Another interesting annoy bug that I noticed in Parallels. This is not one time, it happens every time. When I have the Windows Vista running in Parallels and if I keep it idle for few hours then you can’t do anything with that OS when running under Parallels. The OS will be grayed out, and will not respond to any keystrokes or mouse events. It happens either in full-screen, windows or coherence mode.
The only option left is to quit the Parallels and restart the OS back. They should let user know that the OS is in sleep mode; and should allow to start the OS directly, by identifying the underlying OS state.