That happens due to everyone thinking that the RC1 and RC2 downloads are the full "working" versions of the new Windows. They are not! The beta versions are just as they are named "Beta for Evaluation Only"! All they were released for was "evaluation" and not to run as a primary OS. The problems being seen there are due to the unfinished version's lack of support. You may have to remove and reinstall the beta if you can't correct the problem by manually removing the new values created to load the intended program.