Check out our guide on how to convert MP4 files to AVI, whether you use Windows or Mac OS X.

I was recently sent some video clips in .mp4 file format and could not open them with Windows Media Player, which displayed a message saying the file was incomplete or corrupt. I tried various ...

When you export a Windows Live Movie to disk its default settings go out to an MP4 file. Windows Media Player on his computer does not play MP4 files.

Windows XP users, for example, typically run the operating system using an administrator account. One bright spot, said eEye, was that because Winamp does not open MP4 files embedded in a Web site ...