Ive had the same problem, windows media player is becomeing more obselete regardless of the version, even if it manages find the required codec it is rarley able to utilize it and play the file. I would suggest downloading DivX at DivX Video Player - DivX Video Codec - DivX Converter Its free and It will play many more files than WMP. The only problems ive had is the audio track will occasionally wander out of sync with the video.