Just upgraded to lion. Starts up fine, then suddenly the clock stops and I can't open anything from my HD to my activity moniter. I can still reset and shut down. Have tried everything: Disk repair Permission repair Pram reset Smu reset Reinstall lion Nothing works. I made a new user but I can't do anything with the menu there too, can't check the clock box so it appears in the menu and when I do check it for blue tooth blue tooth does not appear. Everything works fine in safe mode. The problem is with the system preferences menu items. Clock, sound, blu tooth, ect. If I can fix these I think my computer will stop freezing.