Is Your Mac Running Slow? Try to Repair Permissions

OS X provided Mac users with a new modern operating system with the old foundation of UNIX. One of the benefits of UNIX is it’s multi-user capablity. To manage the users of the system, UNIX uses file ownership and permissions. Ownership and permissions is a large subject unto itself, so we will not address the details here. Look for a tutorial in the future or go to for additional reading.

Occasionally in OS X some key file ownership and permissions get changed for whatever reason by applications and more frequently, program installers. When ownership and permissions get changed, things just don’t work as they should. The symptoms might be programs quitting unexpectedly, preferences not being remembered, programs not launching, etc. This is where Repair Disk Permissions utility comes in. This utility, which is part of the Apple Disk Utility program, corrects the ownership and permissions according to Apple specifications. Frequently, this corrects many system and program errors. Repair Disk Permissions is a OS X specific utility and UNIX does not have such issues. Hopefully, this a concern and procedure that will go away in the future. For A step by step tutorial read below

To repair permissions, open the Disk Utility program found in the Applications>Utility folder on your hard drive root level directory. At the top of the Disk Utility window is a row of tabs. Click on the First Aid tab. On the left is a list of the disk and volumes mounted on your computer system. In the example below, I have two mounted volumes – one named SHHD and another named Media.You will need to click on your boot volume to select it. Only boot volumes can have permissions repaired.

Disk utility

If the buttons labeled “Verify Disk Permissions” and “Repair Disk Permissions” are grayed and not selectable, you have not selected the boot volume or you are not a system administrator. To allow system administrator approval to repair permissions, click on the padlock button on the lower left and enter a system administrators name and password.

Once you have selected a boot volume and have system administrator privileges, you can go ahead and click on the Repair Disk Permissions button. You will see the process begin with messages in the center window and a progress bar below it. This process may take a while so it may be a good time to go for coffee.

Repair Permissions

Once done, you can quit the Disk Utility program. You do not have to reboot the system for the changes to be effective. It is recommended that you repair your disk permissions after installing new programs or once every month or so of normal usage.


  1. Brian

    I too “reparied permissions” and had instant success – internet was running fast again.

    BUT this doesn’t last. The internet gets slow again (painfully slow) with in an hour or so.

    I again perform “repair permissions” – and a lot of java permissions get repaired, etc. and the internet is fast again.

    Any suggestions to make this solution to my internet speed problem permanent?

  2. ranvirkumar

    Removing unnecessary plug-ins of my Mac applications with Stellar Speed up Mac helped me to speed up my Mac.

  3. After 12mths or less depending how much you use your Mac, I find if I run the Mac disk utility every month it really helps keep my Mac up to ‘speed’. Also you save stuff to your desktop the don’t! This will slow down your Mac. If all else fails then Download MacKeeper it definitely is the best software out there for the Mac to keep it in peak performance.



  4. Jeff

    Where do you save your files to if they’re not supposed to be on your desktop?

  5. Hollie Hirsch

    Mac keeper is a virus !

  6. Bob Barren

    My mac does not have “Disk Utility” under applications or anything of the sort. Please help ? 🙁

  7. Jim

    The “Disk” is stored inside the “Applications -> Utilities” folder

  8. carmen

    I was keeping up until he got to the part where it says on the left is a list of disks and volumes… please help!!!

  9. idiot

    @ Carmen I was having the same problem… check the picture out carefully (notice its highlighted in blue), you have to click the name of the Hard Drive on the list to the left then the Tabs come up

  10. Phoebe

    I downloaded mackeeper, but have deleted it after I realised I had to pay for it, is it a virus? how can I find any left over files if there are any on my mac?

  11. morgan

    Mackeeper is NOT a virus, its a program to keep your mac in peak performance. and you do not necessarily need to buy it, they have free downloads of it around
    ( Link: )

    i dont know what i would do without this program, those who say its a virus are just messin with ya

  12. Chiquita

    MacKeeper has my Mac running flawlessly! Thanks for the help!

  13. Daniel

    MacKeeper is a a software that is not a trojan, but it doesn’t perform like it should. Read up on it!
    Be careful and cautious with this software. Use Coctail, CleanMyMac or any other software that has been around for years that you can trust by reading years of reviews.

    Good Luck

  14. Tony Sale

    Just repaired permissions it was a great help – thanks!

  15. Trish

    I dont know which one is my Boot Volume or Boot Disk..

    this is what I have – something called:

    320.07 GB Hitachi HTS……… media

    and another called:

    Macintosh HD

    Which one am I supposed to fix?

  16. Andy

    I did a speed test on my wife’s pc and then my iMac. Her internedt connection was 20mps and my Mac was 9mps. I have lots on my desktop, 420GB used and only 80gb free on the hard drive and I run lots of programs like reason and logic… I try not to use the internet too much but when I do I want it to be fast… I’m thinking I might just do a complete system re-install but with all the programs and so on this is a full days work…

  17. beginner

    I’ve done a PRAM (Controle+Option+P+R) and my iMac do not starting up anymore. It stays like “searching” all the time, showing the apple and the small circle permanently moving around itself, indicating that is trying to solve some problem.
    I can’t put a boot disk, because there is another disk inside. I don’t know how to put it out with keyboard shortcuts.
    How can I fix it and obtain the effective starting up?

  18. Clean My Mac

    I have been using CleanMyMac software for years. It works great!! for details.

    CleanMyMac has been around for years and i must thank them for keeping my wifey from saying “my Mac is running slow again – why??”.

    So thank you!!

  19. Cara

    My computor wont let me repair permissions i have had problems for a long time now you give permissions to all users and it changes them back. i have just got a new i pod touch and my computer will not let me download the new itunes it says installer is damaged and does not have correct permissions can anyone help have had a problem with the permissions for a long time but is now a real problem

  20. Thursday Things

    […] 3. My Mac was running really slow, Firefox was freezing, internet pages were loading terribly slowly and after checking my router, and doing my own little series of diagnostics and trial and error rule-outs about what I thought may be the problem, I found this info about repairing permissions: […]

  21. Yvo W.

    Stellar Speedups automatic script
    removed some very important files from my computer to thrash..

    however i cant open some apps now including adobe acrobat reader and apples preview..
    some of my printers only have menu language set to spain.. ?!?

    So WTF!
    now i have a thrashbin full of actually important files and dont know where they should go back to in my library…

  22. Scott

    Saved me from throwing my wife’s iMac out the window…and what little hair I have left!

  23. Bill

    Sounds like there are no solutions. Everyone is split on what works and what doesn’t. What do we do for help when there is none…..

  24. scott

    Apparently you’re all rather retarded when it comes to using your comp. Another classic case of having more money than sense. way to go.

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