I have a new 2.2GHz MacBook. Whenever I try to shut it down, it hangs at the screen with nothing but wallpaper and the working circle. It'll sit there for eternity. I installed InsomniaX; does that have anything to do with it? Next up, software update hangs at 'checking for updates.' Every other internet-enabled application works fine. Logging in under a different account works, but I only want one account. It's pretty stupid to have to maintain two accounts just for software updates. How can I fix that?