How to Repair Mac Hard Drive and/or File System When Disk Utility Can’t

Hard Drive Issues on a Mac – A Rarity, but a Pain Nonetheless

Earlier this week I received a call from a local business client who was having problems publishing a self-maintained website for their store. Although my service call began with troubleshooting a problematic website, the situation promptly escalated to showing symptoms of a serious hardware issue.

At first it seemed like the Macbook Pro owner’s issues were purely related to iWeb and needing to be properly configured for their web hosting account. It wasn’t long before I discovered that her Mac was having issues accessing files from its hard drive. And that’s when it happened…

Upon a system restart, the Mac would not boot past the initial gray screen with Apple logo, spinning wheel and frozen progress bar.

It was quite obvious the computer was not successfully accessing its operating system files but it was too early yet to be sure whether it was due to mechanical issues with the hard drive or motherboard, missing or corrupted files stored on the hard drive. I was going to have to narrow it down before making a diagnosis that could cost the client unnecessary data loss, expenses for hardware or labor.

I would suggest the following steps that I tried prior to assuming a hard drive failure:

1. Attempt to repair your system drive using Disk Utility.

Obviously if you are stuck at the gray screen of agony, booting past it isn’t an option. But you can boot from your system disc labeled Mac OS Install DVD. To do so, pop it into your optical drive and hold the Alt/Option key while you power up the computer. Keep holding it til you see your boot drive options and then click the Mac OS Install DVD to boot from it. Once past the language selection, you can access utilities from the top menu. Disk Utility is the one you want. When it opens, click on your hard drive in the left column sidebar and the click Verify Disk followed by Repair Disk under First Aid. If your computer completes its process, then it might just be your lucky day. You should now initiate a normal restart to see if your problem has been resolved. But if your situation is like mine, you might get failures indicating the hard drive is unreadable. Pass go, but do not collect $200.

2. If you DON’T have a Mac OS install DVD OR you DO have access to another Mac and a firewire cable, try booting in Target Disk Mode.

This is when you boot your afflicted machine as though it was an external drive to a healthy Mac. To do so, first turn on your sick Mac while holding down the T key and you will see a gray screen with a large occasionally moving Firewire logo. You can now connect the two computers via firewire cable and boot the healthy computer while holding the Alt/Option key as described above. Your sickly computer’s hard drive in target disk mode should appear as a boot option on your healthy computer. Choose it and proceed. If you are able to boot to it successfully, you can try again to run Disk Utility from Applications->Utilities and to verify/repair the hard drive. If this works without a hitch, again try and reboot your computer normally to see if your problem has been solved. If not, keep reading.

3. This option is the one that surprisingly worked for me: Boot into Mac Safe Mode while showing its progress in a command line UI.

Your Mac will automatically attempt some more gloves-come-off disk repair measures when you boot into safe mode.

To start up into standard Safe Mode (to Safe Boot), do this:

  1. Be sure your Mac is shut down.
  2. Press the power button.
  3. Immediately after you hear the startup tone, hold the Shift key. The Shift key should be held as soon as possible after the startup tone, but not before the tone.
  4. Release the Shift key when you see the gray Apple icon and the progress indicator (looks like a spinning gear).

To start up into Safe Mode with display of the progress in a command line UI, do the same as above EXCEPT hold the Command and V keys along with Shift.

In my case this process worked and I was able to boot into safe mode with the affected computer. You can now restart the computer as normal and you will likely be able to boot now, possibly after a brief progress bar display during bootup. If this works for you, you should still be concerned! Even though your computer is working seemingly normally, you should consider yourself blessed (I don’t do luck). If you’ve found my advice helpful so far, heed my next directive: use your extra life to immediately make an entire Time Machine backup onto a reliable clean external hard drive. You will need this if/when your hard drive crashes if you want to recover your documents and/or applications.

If none of the above worked for you, it may be time to bring out the big guns if you really need to save your data.

4. Try an advanced data recovery software such as DiskWarrior or Disk Drill.

Short of sending your hard drive to an expensive data recovery specialist, this might be your last resort for a DIY fix. These solutions may require you to remove your hard drive, use a live boot cd or target disk mode. You should refer to their respective developer’s website for a thorough outline of the process.

In Conclusion and in Summary

In any case, there is a reason your hard drive is having these issues. Replacing your hard drive very soon should be your plan especially if you have a hard drive more than 3 years old and you don’t have a strong hunch that you caused your own issue in any way.

My Recommended Hard Drive Purchase to Fix or Upgrade Your Macbook

I recommend Seagate Momentus 7200 RPM hard drives and I use them in my own and client’s machines. Replacing my original Hitachi hard drive (which had incidentally NOT failed, but was critically full at only 160GB) truly breathed new life into my Macbook Pro. Not only did it provide tons more storage space for me, but the 7200RPM performance and larger 16MB cache has greater responsiveness and performance.

Did this article help you? Want to say thanks? Send a little thank you.?


  1. Hey, Great Article!

    I’ve heard mixed replies regarding the use of the Seagate Momentus XT SSD drives. Have you had any experience using/installing these? I have a 15″ MBP 2006 still going strong but looking to doing some upgrading.


    1. Anthony, I’m sorry for the delay in response! I actually do not have any experience with the Seagate Momentus XT SSD drives. I did research them enthusiastically when I was choosing my replacement hard drive and decided that it either wasn’t beneficial or even potentially problematic in my Mac. Did you make a decision to buy one? I’d love to hear your feedback on them!

  2. Hello!
    I followed all your instructions and got the hard drive repaired. But when tried safe boot…apple and spinning wheel came on screen but after few minutes the apple turned into a circle with a slash line in it and the progress indication is still spinning…what can I try next?
    Thanks a lot,

    1. Jyotsna, I’m sorry to hear that you’re still having trouble with your Mac. The particular errors you are having might indicate that there was some physical damage to your hard drive. I don’t want to issue that diagnosis, but generally when Mac Safe Mode and software-based utilities cannot repair your data your hard drive may actually be beyond repair or require extensive physical repair internally to salvage them. If you got it solved, please let us know how you did so!

  3. Hi Kyler, surprisingly the same solution that fixed the issue for you seemed to work for me as well. I have no idea how or why but it did. Thank you for posting all of this, I’m going to upgrade my hard drive anyways now just to be safe, and I was wanting to already. You saved me a lot of time and headaches.


  4. David, I’m glad that it helped you out! I can still remember feeling surprised when it worked out somewhat painlessly in the end. Enjoy the newly reinvigorated reliability of your Mac! -Kyler

  5. Kyler, you saved me a ton of grief!. Desperately looking for help I searched Mac Hard Disk Recovery and luckily found your article. The instructions for starting in Safe Mode with Command, V and Shift worked for me! I had previously tried Safe Mode start and nothing happened with my blank screen. After messing with my Mac for hours, thinking the HD was blown and getting quotes for repair, I found your site! Your instructions were perfect. Thank you so very much!!

  6. Read your tutorial and it really helped alot. Very descriptive and helped me get further than i was able to get on my own. Thank you!

  7. We use two tools: one for index repair and one for surface scanning and drive troubleshooting. For index repair we use Disk Warrior, which has been mentioned. For surface scanning we use Scannerz, which is a new tool. Both of these are dedicated to their specific tasks and do excellent work. Scannerz is new, I think it’s only a year or two old, and Disk Warrior is ancient.

  8. Thank you so much! I had tried everything with no luck and the Safe mode with Command line UI worked to repair my disk problem!

Comments are closed.