This is where theCombined Community Codec Packcomes into the picture.
Launch the setup process, and you should come to the “Select Components” dialog.
We’re trying to play this under WMP11, afterall.
This is the component that actually will help you play your OGM files.
Just installing the codec pack doesn’t set OGM files to Windows Media Player though.
check that you’ve checked the option to always play in WMP.
And there we are… OGM files playing in Windows Media Player.
Download Combined Community Codec Pack