|WMP11 for XP doesn't support MP4. Windows 7 + WMP12 does, but I wouldn't suggest running Windows 7 on the older hardware without upgrade, which isn't worth your $$$ to play MP4. |
WMP supports the following: http://support.microsoft.com/kb/316...
"The MPEG-4 file format, as defined by the MPEG-4 specification, contains MPEG-4 encoded video and Advanced Audio Coding (AAC)-encoded audio content. It typically uses the .mp4 extension. Windows Media Player does not support the playback of the .mp4 file format. You can play back .mp4 media files in Windows Media Player when you install DirectShow-compatible MPEG-4 decoder packs. DirectShow-compatible MPEG-4 decoder packs include the Ligos LSX-MPEG Player and the EnvivioTV."
You'll need to get the codecs for WMP11 to play MP4, or like mentioned above, get another player that has the codecs built-in. Everyone recommends VLC player, as mentioned by DAVE
Thanks for any input.