Dan Frakes at Macworld does some heavy lifting this week with “Repairing Permissions: What you need to know.” Required reading:
The procedure has taken its (rightful) place in the Pantheon of Overused Procedures, next to “zapping the PRAM,” “rebuilding the Desktop,” and “performing a clean install,” with some users acting as if it’s a cure-all for any and every issue anyone might have with a Mac, and something that should be done every day to prevent problems from ever occurring…The truth about repairing permissions lies somewhere in between. We’re here to help you find it by taking a closer look at repairing permissions—what the function is, what it does, when you should do it, and when you shouldn’t.