try to install my decoding pack, it's in frensh but easy to understand and it can decode lots of vidéo file included all real file, mkv, mp4, mpeg4, vp6 .... it's a pack of filter so it won't distrub your codec install ++
http://satsuki.yatoshi.free.fr/
download =>
Satsuki.Decoder.Pack Version 1.0.1.9 (4.29Mo)
give it a try, i think it's a very usefull pack, i might trad it in english someday ^^
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