I seem to have this problem with Windows XP. For opening mp3s and playing an audio CD I've set Real Player as the default program for these files. But every once in a while it just switches itself to MM Jukebox. Probelm is I deleted MM Jukebox cause I hated it so much, so when it decides to switch the default to that program the file won't even open. I need to be able to fix it so that my computer doesn't think it still has Jukebox and so it doesn't go switching defaults that I've already set.