When attempting to playing a movie file, such as an AVI, you may find that the audio and/or video doesn't play because of a missing codec. One solution is to use a audio/video player, such as VLC, which has built-in support for a wide variety of audio/video codecs. Or, if you prefer to stick with the media player you are accustomed to, such as Windows Media Player, then you can use a program, such as GSpot to identify the missing codec.
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