Same problem here with movie studio. I NEVER had problems with activation since version 7. Now I need to edit a video file and I CAN'T just activate a purchased software!
It doesn't help! After I purchased version 16 it was successfully activated. Lately I reinstalled windows as well as vegas that came with music maker. TODAY there's no video software installed except music maker though I installed it! I installed vegas and keep failing activating it. Please fix it!