
Also from Apple:ĭisk Utility 12.x: Repair disk permissions Once the repair has finished you can safely exit Disk Utility. It should take a few (or quite a few) minutes to perform the repair, and if you have the Show details button checked, you’ll see any irregularities as they’re found during the repair. With the hard drive selected, click the Repair Disk Permissions button. Next, select your hard drive from the left panel of the Disk Utility window. Launch Disk Utility, search for it via Spotlight or navigate your way to it via: Macintosh HD > Applications > Utilities > Disk Utility

How to Repair Disk Permissions in Disk utility
