http://www.techdigest.tv/2006/07/diagnose_media_.html
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Who amongst us hasn't had problems playing back media files, be they
MP3s, DVDs, AVIs or audio CDs? Yes, we've all been there and
resolving faults in media players can be a nightmare. A lot of the time
it's down to missing or faulty Codecs.
They're the little add-ons and plug-ins that media players rely on to
untangle the coded or compressed code in a media file. The thing is, if
your PC is anything like Propellerhead's you probably have shed-loads
of them, but there's usually no easy way to see what you've got, or
if they're all working properly, which is where Sherlock - The Codec
Detective comes in.
<SNIP>