I am running 10.7.4 on my mid-2011 iMac. When I went into Safe Mode today, all my Icons and Folders showed up on my Desktop, however, the Menu Bar at the top didn't. I had to push the power button to put it to sleep, take it out of sleep, and then sign in again. After I did that, the Menu Bar then showed up at the top. I repeated this twice. Ideas?