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My wife has been complaining about her MacBook Air's performance. It seems to work fine, but when I ran Disk Utility and did a "Verify Disk", it reported filesystem errors. The "Repair Disk" button was disabled, because this is the startup drive.

So, I restarted with the Mac OS X Install Disc and ran Disk Utility again. When I run "Repair Disk", I get this output:

Verify and Repair volume "Macintosh HD"
Checking Journaled HFS Plus volume.
Checking Extents Overflow file.
Checking Catalog file.
Invalid node structure.
Volume check Failed.
Error: Filesystem verify or repair failed.

Is there anything else I can do to try to repair the filesystem (besides erase and reinstall)?


FWIW, here's what happened after I asked this question:

  1. Restarted in single-user mode (Command-S on boot). "/sbin/fsck -yf" gave more error messages. And when I did "exit", I saw error message "disk0s2: I/O error" followed by "CPU Halted".
  2. Tried to reboot. Apple logo appeared, and wheel spun for about 15-20 seconds, then machine turned off. This repeated every time I tried to reboot with the internal disk.
  3. Tried resetting PRAM (Command-Option-PR on startup). No change.
  4. Called Apple. The expert walked me through SMC reset, which did nothing. Tried to do an "Archive and Install" re-installation, to save original disk contents, but the Installer refused to install on that drive due to filesystem corruption.
  5. Did an erase and re-install. (And my wife now hates me.)

I'd still be interested to hear if there is anything more I should have done.

share|improve this question
When booted from the install disk, does running the verify first tell you any more specific information? – Troggy Aug 16 '09 at 23:35
No, that's the only info I get. Called Apple, and the "expert" told me the disk was corrupt and I'd have to erase and re-install. – Kristopher Johnson Aug 17 '09 at 0:14
up vote 8 down vote accepted

If you ever run into this problem again I highly recommend DiskWarrior - it's worth the price tag over and over. It's saved several systems for me from directory corruption.

share|improve this answer
I've added my vote here, Diskwarrior is excellent. Unfortunately Apple will never recommend third party tools and they definitely overdo the 'erase and reinstall' line. – alimack Feb 22 '10 at 10:57
Apple DOES recommend 3rd party utilities, as part of Applecare. Applecare includes a copy of Tech Tool Pro. But Apple can't recommend one product over another, otherwise they are "biased" or "Trying to put one business out of business, vs. the other". But, yes, I agree they recommend Erase & Reinstall too often. – Benjamin Schollnick Feb 22 '10 at 22:32
Apple includes Tech Tool Deluxe (a subset of Tech Tool Pro) with each Applecare agreement which is distinct to recommending it. You can upgrade to Pro for a fee. In fact Tech Tool Deluxe has failed to detect hardware errors that Apple's Hardware test has found in my experience! – alimack Apr 12 '10 at 10:46
I've tried everything and nothing worked except for DiskWarrior. Highly recommend!! – macek Jul 4 '10 at 3:42

Before buying DiskWarrier, you should know that the download version of the app cannot burn a bootable DVD. You have to wait for them to ship this out, and this can take weeks. DiskWarrier's website conveniently hides this information.

If you have AppleCare you can download a program called TechTool Deluxe, which I hear does create boot disks, and also has a bunch of other disk utilities on it and may help.

share|improve this answer

I second the Disk Warrior answer... But it maybe simply that your hard drive is dying... Boot from the Installer disk -> Continue -> Tools -> Disk Utility. Highlight the hard drive (not the partition), and see if at the bottom of the disk utility window, does it say SMART FAILURE? Or is the disk highlighted in red?

If so, then the disk is dying, replace the hard drive, and hope your backups are recent... (You do have backups/)...

share|improve this answer
No SMART failure. We've reformatted the drive and re-installed everything. We'll see how it does. No backups, unfortunately (I didn't know that my wife expected me to make backups for her laptop). – Kristopher Johnson Aug 18 '09 at 16:46
Worth noting that if you have another Mac with an external drive and a wireless network, you can backup wirelessly using Time machine. You don't need Time capsule. And wives never tell you they need backup - you're supposed to read their mind! – alimack Feb 22 '10 at 10:55

This has happened to me, grab yourself a copy of SuperDuper.

share|improve this answer

Boot from the installer CD. Disk Utility cannot repair the active startup disk.

share|improve this answer
I did boot from installer CD. See second paragraph. – Kristopher Johnson Aug 18 '09 at 15:34

You never check the disk you are booted from. Boot from another disk and then verify/repair.

It is like doing open heart surgery while you're ...jogging.

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"I restarted with the Mac OS X Install Disc and ran Disk Utility again." – JoshP Nov 14 '12 at 20:37

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protected by Community Oct 22 '14 at 12:01

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