.avi on windows media

I want to play an avi movie on a windows media player and i dont know the codac....Help!

I have the same problem. I have Win Media Player Ver 9. But it does not play some AVI files. Which CODEC will I Need? Can some body help me find that out?
Thank you.

Try one of the tools listed on this page to determine the codec you need.
http://www.moviecodec.com/questions/neededcodec.html