01a.m4v

: If the file is unprotected (no DRM), you can often simply change the file extension from .m4v to .mp4 manually.

: For protected or stubborn files, use tools like: 01A.m4v

: Use the "Convert / Stream" feature to export the video as a standard MP4. : If the file is unprotected (no DRM),

: A free, open-source tool widely used for converting M4V to more universal formats like MP4/H.264. 01A.m4v