Codec error in vista media center....help!

Just trying to watch some videos using Vista Media Center, I just did a clean install and haven't had any problems in the past but this time for whatever reason I get an error stating windows can't find an appropriate codec to play the videos (which are avi's). I've tried multiple codecs ffdshow, divx, x-vid, etc and haven't had any luck. I do get videos to play just fine in media player 11 though. Any ideas?

Thanks.


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just tried running windows xp decoder checkup utility and it states that my nvidia video decoder is selected for the
prefered decoder. I'm also trying to use a program called Vista Media Center Decoder utility and select the nvidia decoder but for whatever reason I cant detect the nvidia decoder with this program. Can anyone give me advice here?