How Can I Watch an AVI File Using Windows Media Player 11?
When you upload a video file from a digital camcorder or download a video online, it may be saved as an Audio Video Interleave, or AVI, file, a common video format. If you try to play an AVI file in Windows Media Player 11, however, you may be missing the audio or video portion of the file. Though Windows Media Player 12 supports AVI files, Windows Media Player 11 requires a third-party codec to play them.