A few weeks ago I had a severe issue with my laptop, and posted a question here detailing my issue: Prohibition Sign and Can't Reinstall OS X

Today, a friend of mine was having very similar issues which prompted me to run First Aid using Disk Utility. The message I received was "First Aid found corruption that needs to be repaired" with instructions on how to do so. I then restarted my laptop, and lo and behold, it would load up partway and then just shut off. Restarting several times yielded the same results.

Booting into Recovery Mode once again didn't work -- no option to re-install & verify/repair disk on there was useless. Used Internet Recovery mode which proved just as useless. Booted into single user mode and ran "fsck -fy" like last time, except this time I kept receiving "The volume Macintosh HD could not be verified completely." along with Disk I/O errors.

Tried running several variations of fsck_hfs -r /dev/diskxsy to no avail -- kept getting Disk I/O errors & the messages "corruption was found and needs to be repaired."

By absolute dumb luck, I came across an obscure fix that worked: https://discussions.apple.com/message/23205771#23205771?ac_cid=tw123456%2323205771

I followed the instructions there and it finally worked. I immediately ran First Aid again, and received the exact same original error message. Obviously, I am terrified to restart my computer or try anything, so I'm at a loss at what to do, other than make a backup. My SMART status is Verified. Any help appreciated!

  • SMART generally catches drive deaths, but it's not the be-all end-all of everything. This absolutely sounds like a dying drive. Backblaze did a good study on the issue.
    – JMY1000
    Feb 14, 2017 at 16:46
  • @JMY1000 What do you suggest? A new drive?
    – Luke James
    Feb 14, 2017 at 18:21
  • Yup. If your computer is under warranty, go to Apple; if not, time to go shopping.
    – JMY1000
    Feb 15, 2017 at 2:00

1 Answer 1


Based on your other question (which you seem to have posted from a different account) and the circumstances surrounding this one, I feel your hard drive is at very high risk of failure.

I would immediately make a full backup of your hard drive.

Once you've made the backup you should satisfy yourself that all of your most important files have been successfully backed up.

Then, as a minimum, I would do a full reformat of your internal hard drive. However, when you do so, don't pick the easy option. Instead click on Security Options and use the slider to choose how many times you want to write over the hard drive. No need to pick anything too high, just enough so it's not formatted in only seconds but instead writes over the entire hard drive.

I suspect that following this process will fail and you won't be able to securely erase the drive. If that's the case, it's time for you to replace the internal hard drive. This is not too difficult (I'd say about medium difficulty) and you can even choose to upgrade to a SSD if you want.

If, on the other hand, you can successfully securely erase the hard drive, then proceed to re-install your system from scratch. Afterwards you can restore your data from the backup you made (however, do not delete your backup).

Let us know how you go.

  • By backup, do you mean just transferring over the files to a drive or a TimeMachine backup? I'm scared that something in my file system is corrupted or something and if I restore from a TimeMachine backup it'll restore it with the same corruptions/issues. Thank you for the suggestion; I will try reformatting, but I have no idea how to go about re-installing the OS from there if it won’t show up in the menu in Internet Recovery Mode.
    – Luke James
    Feb 14, 2017 at 17:43
  • If you do a Time Machine backup and then go ahead and do a totally fresh installation of your system, then you shouldn't have any issues migrating data back from the TM backup. Your system itself won't be migrated back from TM, only your files etc. If you don't already have backups previously, I would probably do a full TM backup first and then manually copy across your most important data onto another drive. But if you've already got corruption on your main drive there's nothing you can really do about it now (unless you have older backups).
    – Monomeeth
    Feb 14, 2017 at 21:17
  • As for installing macOS on a new HD, you can do this by using Internet Recovery. Another options is to download the installer using another computer and create a bootable USB. Or you can start your Mac in Target Disk Mode and use another to do the installation. Either way, you'll find answers here on how to do the installation.
    – Monomeeth
    Feb 14, 2017 at 21:17
  • Hello again. I ordered a new SSD and was waiting for it to arrive to try this... and the high security erase worked (I actually did it a few times to make sure, and once on the highest security setting). It's now recognizing the original drive and allowing me to re-install OS X on it, and Disk Utility says it's fine. Is it possible this is a fluke, or should I no longer bother with the SSD? Sorry for the bother again.
    – Luke James
    Feb 23, 2017 at 1:19
  • @LukeJames I guess that is a personal decision based on what you can afford and how important the data is to you. If it was me, I'd keep the new SSD and install it into the MacBook and use that as my main boot drive. I'd then keep the old drive and use it in an external case/enclosure as another drive. Cases/enclosures don't cost much at all. But, as I said, it's a personal decision for you to make.
    – Monomeeth
    Feb 23, 2017 at 1:25

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