Project won’t render

Hi there,

I am having extreme trouble with your Window Movie Maker program, for the last two days I have attempted to save a project and render it to upload onto YouTube, however it does not save as it continues to say that I have missing or unusable files within the project which I know is not true. This has happened many times and as i have used your movie maker to edit many of my videos with success it is very frustrating.

Please help as i need to upload this video as soon as possible.

Thank you