Yesterday I downloaded and installed the latest Parallels 9 release. Afterwards, I got an error on Win7 login that said "C:\Windows\System32\PropSys.dll is either not designed to run on Windows or it contains an error". The login screen for Win7 won't come up. I reinstalled the new Parallels and the previous version I was running on with no change in results. Can you start Safe mode in Parallels? If so, I might be able to replace the dll with one that works. Any other ideas would be appreciated. No, I wasn't bright enough to take a snapshot before installing the new Parallels. Should have finished my coffee before doing it. I'm using the OS X 10.8.5, Parallels Desktop 9 with Win7 as the VM OS. Everything worked fine until I loaded the newest update to Parallels.