When you tell Movie Maker to upload to YouTube, it does two things:
- It creates a file containing the final contents of your movie ready for uploading to YouTube.
- It uploads that file to YouTube using the credentials you supplied.
The process could be failing on either step and since you said you were having trouble saving the movie at all, it seems like the problem is probably in the first part.
Let's split this into two steps to isolate the issue. First try saving the movie to your PC using File > Save Movie. Choose the default format that is best for your PC.
Now keep track of how far it gets (%) and what error it gives. We need that information to help you further.
Most likely there is some incompatible source file that is causing Movie Maker to be unable to save the final movie. If you know that it fails at 50%, for example, look at the clips in the middle of your movie. If it fails at 10%, look toward the front,
etc.
If that all succeeds and you are actually able to save your movie in .mp4 format, then try manually uploading the movie to YouTube by logging on to your account and using the Upload facility. Make a note of any issues you encounter there.
