I have Win xp media center and have microsoft framework 1, 1.1, 2 and 3.5. I have the Clean Installer before and it was fine. I reformated my drive and know I cant install, I get a Fatal execution engine error 0x7927f26e at the very end of it. It even makes the desktop shortcuts and everything but if you try to click it I get the same error. I have tried ot install older versions as well and have the same issue. I cleaned the registry so it was empty and restarted after that before I installed. Does anyone have any suggestions?

This is most likely a dotnet framework issue. I would recommend to completely uninstall the 1.1 framework and reinstall it.