I imported several clips from my android (mp4). I can edit and play it in the program but when I go to render, it hangs in the first few seconds, then crashes. I assume there is some incompatibility so I used another program to edit and render in a wmv file and avi. When I bring the wmv or avi file in and try to edit..it works but when I go to render it, it crashes the same way! What is going on?

I am very frustrated and hope you can help.