Media Player

Hi !
I would like to know how to make my Media Player 7 Beta play mp3.
In a previous answer I was shown how to associate the file to player etc.
But when I do that I am asked to look for a player that I had tried a while back COOL PLAYER. So now when I try to associate the Windows Player to the mps it always asks for the COOL PLAYER which of course it can not find. Any ideas on how to correct this.

George