Sometimes, we get the error when saving movie of Windows Movie Maker. I capture the screenshot below. The error information is: "Windows Movie Maker cannot save the movie to the specified location. Verify that the original source files used in your movie are still available, that the saving location is still available, and that there is enough free disk space available, and then try again.".
The probable reasons of this problem are:
Not enough computer memory for the processing of your project, combined with other tasks your computer is doing such as it renders the movie.
Using source files which don't work with Windows Movie Maker, or the files are corrupt.
There are other reasons also. You need to do some detective work to be sure you're resolving the right issue the right way.
Other causes reported by users:
Some users reported their issues resolved by reinstalling the Windows Media Player... I don't understand the relationship between Windows Movie Maker saving videos, but want to pass it along. And It does work for many users.
And many users of "Folder Lock" software have problems when the locked folders include those with the source files used by a project. So make sure your source files are not locked by any type of "Folder Lock" software.
You can also find a discussion thread here .