Major problems with iTunes Installation!

[technomann]

Even if its DRM you may still be able to remux the streams into another container. Not sure, though.
Just a sidenote, remuxing isn't the same thing as converting/re-encoding streams.

Download and install mkvtoolnix and follow this old attachment I uploaded for another thread some time ago:

(Ignore the append option unless you have several video files of the same resolution, audio and video properties that you want to combine).

Thanks for the suggestion. Remuxing didn't work. If you have any other ideas for converting m4v files I would be happy to entertain them.