Whats wrong with it?

Ok, when I open up my music folder, its got all my music in it but when I click it, nothing happens. In order to listen to music, I have to open WMP, and go to library. I just want to use my music folder. Can someone help. If it means any difference, Im running on Windows Vista.

Are the filetypes associated with Media Player?

They are all MP3 format, but I have them all set to open with WMP. They worked fine up until yesterday. I don't knwo what casued them to stop.