I've been on the computer all day. Something this afternoon, one by one all my programs have gone back to the intro you get when you get new software, safari, firefox, itunes, msn messenger, iphoto, everything. My documents all still there but my photos, bookmarks, movies, music is all gone. The garbage contents are still there. it's osx 10.4.11 2.16ghz intel core 2 duo. I'm at a loss.