In this tutorial, we’ll walk through verifying your permissions and how to repair them if something is wrong. We’ll also look at how to boot to a recovery disk to repair permissions if you find yourself in real trouble. By the end of this tutorial, you’ll see how verifying permissions can be one of the easiest quick fixes for getting a smooth running Mac.
What Are Permissions Anyway?
Permissions are what let the OS know who can do what with each file and folder on your Mac. When those permissions are unintentionally modified, you might find that your applications aren’t launching like they should, you’re having trouble logging in and out, or you’re even having trouble starting up and shutting down.
Even if you’re just seeing a laggy, freezing system, you might benefit from verifying and repairing permissions.
Using Disk Utility
The easiest way to verify permissions is with OS X’s Disk Utility. You’ll find it in the Utilities folder in Applications. Open up Disk Utility, select your disk, and choose the First Aid pane.
Verifying permissions could take anywhere from a few minutes to much longer, but sit tight and let Disk Utility do its job.
Click "Verify Disk Permissions", and the process will begin. If you’ve selected the "Show Details" checkbox, you’ll get a rundown of what Disk Utility is looking at each step of the way. Verifying permissions could take anywhere from a few minutes to much longer, but sit tight and let Disk Utility do its job.
There are a lot of permissions that needed to be verified.
If it finishes and none of your permissions “differ” (differ is OS X speak for “things are messed up right here”) you’re good to go. Grab an iced tea, and feel a little bit superior to all those schmoes with differing permissions. However, if everything didn’t come out rainbows for you, you’re going to need to repair your permissions.
My freshly repaired permissions.
I don’t think I’ve ever verified permissions on my Mac without having to immediately repair them, and it’s not that big of a deal. Just look right underneath the verify button, and click the "Repair Disk Permissions" button.
This again could take just a few minutes or over an hour, and the progress bar won’t always directly correlate with reality, so just let Disk Utility do its thing here. If it just seems to be taking forever and you can't wait to go stream Japanese dramas or something, you can click "Stop Permissions Repair" and return to it later.
When all is said and done, your permissions should be repaired and OS X should be working just a bit better.
Using Onyx or Cocktail
I was hard-pressed to find a good third party app that verifies permissions. All my Google searches for “verify permissions app” came up with OS X’s native Disk Utility, likely because it’s so simple to use, there’s not really a reason to have a second dedicated application for verifying permissions.
Cocktail does so many other wonderful maintenance tasks in one interface, it’s become a one-stop shop for me, including when I need to repair permissions...
If you’re only getting Cocktail and OnyX just to repair permissions, though, it’s probably a waste. You’re better off sticking to Disk Utility if that’s all you need. That said, Cocktail does so many other wonderful maintenance tasks in one interface, it’s become a one-stop shop for me, including when I need to repair permissions, and I know a lot of smart people love OnyX.
When you open Cocktail, you’ll have to enter an administrator’s password, because Cocktail is that cool. Once you’re in, click the Disks tab, and select Permissions. It’s likely your disk will already be highlighted in the dropdown, but if not, choose the disk you want to work with. You can choose to repair permissions for just the current user or for all users.
Preparing to repair permissions in Cocktail.
When you’re all set, click Repair.
OnyX will similarly ask you for admin credentials, and will prompt you to do some maintenance before it even gets started. While it’s great to run these tasks and certainly won’t hurt anything, it’s fine to skip them for now to get to the permissions repair functions.
When OnyX finally opens up, it’s really just a ribbon of options. Select Maintenance, and the Permissions window will open.
Taking care of business in OnyX.
Click Execute, and OnyX will begin its own permissions repair.
Repairing Permissions in Terminal
If you can’t run Disk Utility or a third party app like Cocktail or OnyX because things have just gotten that bad on your Mac, and you’re hoping disk permissions will solve your troubles, you can verify and repair permissions in Terminal.
You can access Terminal in the Utilities folder in Applications. Once it’s popped open, type in one of the following commands:
diskutil verifyPermissions / diskutil repairPermissions /
Permission verification and repair in Terminal.
You’ll get a rotating bar that let’s you know things are popping and an ASCII progress bar. When the progress bar reaches 100% and the process is complete, you’ll get an output letting you know verification or repair is finished.
Working in Recovery Mode
The final way to verify permissions on Mac is by booting to the Recovery HD in Lion or to the Install DVD in older versions of OS X. This gets you out of the OS and allows you to repair any problems you may be having.
This is really useful for repairing your disk when your Mac is refusing to behave correctly or even boot properly, but it can be used to repair permissions if you think that may be the source of some of your biggest headaches.
Recovery mode is really useful for repairing your disk when your Mac is refusing to behave correctly or even boot properly.
To boot to the Recovery HD or Install DVD, restart your computer and hold down the Option key. You’ll be given a choice of bootable disks; select the Recovery HD or DVD. It’s worth noting that the Lion Recovery HD seems to boot up pretty quick, but it was always my experience that booting to an Install DVD took some time.
You may be asked to choose your language, just like the first time you turned on your Mac. I say Tagalog is nice this time of year, but that’s really up to you. You’ll get a few options, including re-installing the OS, but you’re here for disk permissions, so you want to launch Disk Utility.
Once in Disk Utility, it looks pretty much the same as it did when you were running it inside regular old OS X, and the process is the same as above, so I won’t rehash the steps.
When you’re done, you’ll quit Disk Utility and restart your Mac. If the recovery mode gives you any guff, tell it you’re definitely sure you want to restart, and it should automatically boot back to your default disk.
Disk permissions aren’t the end all of Mac maintenance, and repairing permissions will certainly not solve all of your OS problems.
However, some minor to pretty major issues can be solved with permissions repair, and it’s a good tool to keep in your back pocket. Before you resort to more in-depth, more difficult, or even more costly maintenance and repair, verifying and repairing permissions may save you some time and some trouble.