Windows Movie Maker Help!!

Ok, so I'm doing this project for Spanish, and i'm compiling a movie, and so i finished and decided to save it as a WMV. The thing goes to about 48% and then I get this message that says to make sure my source files are still in the same place, which they are, and that my destination has enough space which it does. So, after trying and failing about a dozen times with that, I just gave up and made a new movie, without moving any of the files I used, and I'm still getting the error message.I have to go now, I'll check back tomorrow, but any advice would be much appreciated.