GLad that worked for you. I just had the same problem 2 days ago, and went to that site and got the codec. Which really didn't change anything. Winamp and WMP still couldn't play an MP4 video. Did you just need sound or something? I had to get VLC player (which in itself isn't such a bad thing) to run an MP4. And of course it didn't need an extra codec, 'cause it owns.