So I had the issue where if I would go to launch Forza 7 or FH3 it would come to the splash screen and then immediately crash from there, refusing to start altogether.
I spent some time playing around with possible things I thought could be causing the problem, none of which fixed the issue. As I was beginning to lose hope I tried uninstalling and reinstalling the skype app for whatever reason (windows store version) and immediately afterwards both games returned to their regular working state. I guess there may have been something in the fm7 install file that conflicted with skype or something along those lines.