Up to yesterday, Windows Media would play MPEG-4 (MP4) video files on my laptop (Vista Home Premium). Suddenly, it will no longer play them, showing error message saying does not recognise MP4 files. Could I have accidentally disabled something? Any help would be much appreciated.
1. You may miss the code, download and install K-lite code pack may fix the problem.
2. Or you may convert the video to wmv video for a try, windows media player supports wmv video pretty well. If you don't know how to convert video, I think this step by step direction would help you a lot
http://www.freedvdrip...-zune-cell-phone.html
Hope it helps. Contact me if you have any other question.