I was working on exporting a video from Final Cut Express HD, and continually got a "Error" message. Suddenly my trash starts flashing full and then empty, over and over again and I realize that all of the icons on my desktop are also vanishing and then reappearing. Looking at the dock, I realize the Finder is not running (no arrow underneath it), then will attempt to run for a second, and then quit again. I tried relaunching it, no success. Then suddenly I couldn't click anywhere on the screen. The mouse would move, but it wouldn't click down onto anything - menus and buttons were all locked (and it wasn't the mouse, I immediately tried another). This (the mouse thing, not the Finder quitting/relaunching) has happened to me maybe 3 times since I've gotten my iMac in September, so I did what I'd done in the past - held down the power button and then turned the iMac back on after it shut down. I logged in fine, then when I got in - my dock had completely reset itself. It looks like how it would if I'd just installed Panther, Apple Support link and all, and even a "?" where iMovie should be because of the iMovie HD rename in iLife '05. My immediate thought was "Oh crap - I need to backup". Well I can't. The Finder is still doing it's launch, quit, launch, quit routine. I can't launch any apps that aren't in my dock because the Finder window isn't open long enough for me to click "Applications". And I've rebooted once more since this has happened, and I've reset the PRAM. Nothing. I can't repair permissions because the Finder isn't open enough long enough to launch Disk Utility. I'm officially out of my troubleshooting area of know-how. *Sigh* NOT a good day for my iMac. My precious files! Most of them are backed up, but stuff like iTunes hasn't been backed up for a month. I've learnt my lesson, iMac!!! Now go back to normal! Please help - all stuff appreciated! And I've put this on an Apple discussion, but usually I get faster responses here, so I thought I'd give it a shot here too. Please help!