Windows Movie Maker started to lock up while I was using it. Thankfully, I had recently saved my project. I exited the program and then started it up again. When I tried to open up my project, i got error code 80070057 : Windows Movie Maker cannot open the file... it is not compatible... or.... the file is corrupted. 

Please help because this was a project for school. I was almost done and now it is gone ;( I've tried so many things but nothing seems to be working....