I had problems with TV-Style and rFactor didn't start if it was enabled. I tried everything and it didn't work until I figured out that MSI Afterburner blocked it somehow. Friend of mine had same problem which was solved by shutting down MSI Afterburner before launching the game. I'm pretty sure same happens if Riva Tuner is running as it's based on same code as MSI Afterburner. So it might not be always 7/Vista which causes problems, it might be some program running on background too. Cheers PS. I didn't find anything related to this via search, I hope this isn't here already!