Hey guys, I have pretty serious problem since about two days. I think it happened after installing the last security update (2007-005). I think what happened was that after pressing restart, the computer (white MacBook, about a year old) hung in at the grey screen that appears before it turns of the power. After waiting for a couple of minutes and still nothing happened, I forced it off by holding the power button. After turning it on again, I can login, but most applications don't start anymore. Their icon bounces for a few seconds but then just stops, but the application doesn't start, and there's no black triangle next to it. "Most applications" includes e.g. Safari, Mail, Adium, Skype, Quicksilver, and iTunes. Fortunately, at least Firefox still works so I can write this post. Also iPhoto, the Address Book and the Calendar don't seem to be affected. Oh yeah, the System Update Program doesn't start anymore, too. I already tried repairing the permissions several time but it doesn't help (and actually just says there's nothing to be fixed anyways). Any ideas what could be broken here and how to fix it? Thanks in advance!