Upgraded to Snow Leopard, Parallels won't work

Hi

I upgraded to Snow Leopard and now I can't run parallels. It doesn't launch the virtual machine automatically like it used to, and when a try to Open the virtual machine it just says "Registering Windows Vista" for a long time without moving. When I click on the about Parallels Desktop it says "This copy of Parallels Desktop is currently not active. Please click buy online to purchase a permanent activation key." WTF?? What happened?? I'm running Parallels 4.

 

* Disk utility.app> Repair Permissions

* Reinstall Parallels

* If you don't have the installer for PDM4, download the latest version of 4 here: http://kb.parallels.com/5802

 

worked!

Thank you, re-installing worked.