Parallels 10, Windows 7 and Yosemite 10.10.1 Beta Problem

I'm running the latest version of Parallels 10 with a Windows 7 virtual machine. When I upgraded my Mac OS to Yosemite 10.10.1 beta, I get an error message when I try to open my Windows 7 virtual machine. When I downgrade my Mac OS to Yosemite 10.10, my Windows Machine works fine.

 

Hi Climber,
1. What happens when you try to run Windows 7 Virtual machine is there a error message, please provide us a screenshot of the error.
2. Update Parallels Desktop 10 to latest build as suggested at http://kb.parallels.com/111603 and check if the issue still persisting.

 

I just upgraded to 10.10.1, and I can't use Parallels Desktop anymore. The message says, "You can't use this version of the application "Parallels Desktop" with this version of OS X. You have Parallels Desktop 5.0." Any solutions?