corrupted windows media player library

Okay I seem to have managed to corrupt my windows media player library. It won't add any media files at all or videos. I click on commands and nothing seems to happen, except I can open and close the program. I am sorry to b vague, but yeah it's happened in the last 24 hours and I'm trying to figure how I can repair Windows Media Player.
At one point I've discovered I can't rip music through Windows Media Player either.

Hope this helps. Any suggestions on what could have caused the corruption and how I can fix this?

Cheers, any help would be most appreciative.

Yeah, this happened to me, too. When I add music to the Music Library, It doesn't show up at all in Windows Media Player. It REALLY irritates me, because I want to put music on my mp3 player :'(