I'm using Windows Mavie Maker and I have a problem saving my video.. When I try to save it, it says

cannot complete the save movie wizard

your movie was not saved successfully.

then it says: 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.

I've seen a user having the same problem as me and got a reply that the file format he is using was not compatible with the program. I have all my videos and audio converted to wmv but I still have the problem.. What can I do?