Super User is a question and answer site for computer enthusiasts and power users. It's 100% free, no registration required.

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

Is there a script or process completely reset all file system file permissions to factory default? (Less restoring from a image backup or reinstalling the OS).

I’ve affected all files from / to “Applications” and home folder and all contents. (Everything)

I’ve tried to use the “Disk Utility”’s First Aid “Repair Disk Permissions” but it didn’t seem to touch or affect everything; some but not all. I’ve ran it twice so far.

I’ve seen this thread—“Fixing mac user file permissions, not the system”—but it’s not quite the something.

The reason for all of this is I accidentally ran a chmod on all files (as sudo). Working too fast, now I’m in a hole.

share|improve this question
Which files don't seem to be affected? Only the home folders, or also others? – Daniel Beck Feb 20 '11 at 21:19

I think think that reinstalling the OS is a better option than trying to fix the permissions. You can reinstall without formatting the disk or loosing user data.

Would you really trust your OS after running a script to "fix" all system file permissions?

share|improve this answer
Well as fix permissions is part of the OS I would truest it as much as the OS. – Mark Feb 20 '11 at 22:51
i am having permission problems as a consequence exactly of a reinstall of sLow leopard. – tony gil Dec 3 '12 at 19:40

My opinion, based entirely on a guess, is that your Repair option is not working because the files have the "wrong" permissions to allow the repair to work correctly.

This is not a good position to be in because you have no idea about the stability of the system.

I'd do an Archive and Install installation of OS X (which I guess is what @Chris suggested).

share|improve this answer

Looks promising: fix permissions app

I recommend that you reinstall the OS if something like this isn't available.

share|improve this answer

Reboot your machine from the Install media and do a verify/repair permissions on your boot drive. This should fix your problems. Believe it or not, this is not all that uncommon of an occurrence. While the system is booted, diskutil can't fix the OS partition.


share|improve this answer

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.