I have now encountered this problem. My work notebook has been running PPENG and PEP on Vista without any problems, or any need to adjust compatibility settings.
Yesterday I have rebuilt the notebook. I installed both PPENG and PEP and they worked fine. Last night I went to use PEP and I encountered the problem others have reported.
I can't get either program to work. I have tried various compatibilty settings and turning off Aero, but nothing has worked.
It worked yesterday but not last night. It worked before rebuilding but not now.
