Are you sure you want to start the virtual machine?
One or more kernel components loaded on your Mac are for another version of Parallels Desktop. If you start the virtual machine now, it may work incorrectly. To solve this problem, restart your Mac. If the problem persists, reinstall Parallels Desktop.
Although I could proceed, Shared Networking stopped working, and Windows/Vista crashed a few times. Searching around, found a sweet application to clean the duplicate kernel entries - published by Parallels. Worked fine for me - although note it requires a Mac OS reboot. I did not need to re-install parallels
http://download.parallels.com/desktop/v4/en_us/parallels/update2/Cleanup-Kernel-Extensions.app.zip