Thursday, 17 April 2014

I'd Rather Troubleshoot A Mac Than A PC!

Yesterday I lost another day of my life due to my MacBook Air crashing, just four months after the last hiccup (see Mavericks woes). Of course, the problem this time was subtly different to the previous time - the laptop 'died ' late on Monday night. I lost the mouse connection, and then everything else became unresponsive. It was too late to do anything so I switched it off and went to bed, blissfully ignorant of what was to follow the next day!

First thing yesterday morning I snuck into my office and switched on before going for a shower. Twenty minutes later and the gear wheel was still spinning. I rebooted and the same thing happened. So I started working through my check list of curative actions. Here we go....with notes about the action and outcome...
  1. Reboot in Safe Mode (Hold down the Shift key while powering up*) - nothing
  2. Reboot in Verbose Safe Mode (Hold down Shift and Command + V keys while powering up) - nothing
  3. Reboot into Recovery Mode (Hold down Command + R while powering up) - OK
    1. Run disk utility to repair disk - no problems reported
    2. Run disk utility to fix permissions - no problems reported
    3. Reinstall OS X - after 90 minutes the system failed to restart
    4. Repeat c) - after 2 hours the system reported an error
    5. Repeat c) - same result as c)
    6. Attempt to restore from Time Machine Backup - no Time Machine disk could be located
  1. PANIC
  2. Reboot in Single User Mode (Hold down Command + S while powering up) and run fcsk - no problems
  3. Reboot in Single User Mode and run Applejack - no problems
  4. Reboot and run Apple Hardware Test (Hold down D key while powering up) - standard and extended modes reported no problems
  5. PANIC more intensely
  6. Book Genius Bar Appointment (next slot in 48 hours time)
* For a full set of start-up options see this quick guide from Apple support.

Just for a moment, let's go back to step 6. Why couldn't the system find a Time Machine disk, especially given my tight backup regime? There was a Time Machine disk visible to Disk Utility but it really didn't look very happy. My shiny new 4Tb Seagate Backup Plus disk, sitting in its new Thunderbolt adapter was only showing one partition (there should be two) and that was only 500Gb (it should have been 2Tb).

Of course, whilst in panic mode, I'd forgotten that Seagate Backup Plus drives which are bigger than 2Gb need a special driver to work with the Thunderbolt adapter. In recovery mode, this driver wasn't getting loaded, and so the disk couldn't be recognised correctly. Hence the scary readings from Disk Utility.

To get round this, I had to replace the Thunderbolt adapter with the standard USB 3 adapter and try again. This time the backup drive was recognised and I could restore from the previous night's Time Machine backup.

Finally, the system rebooted although a load of settings had been screwed up. Some licences were missing, a number of configurations were screwed up - all in all, it didn't look much like the machine I crashed the night before. So the last task was to restore the CCC backup from the previous day, reboot one last time, keep fingers crossed and let out a big sigh of relief when everything booted up and looked like it was supposed to.

It just goes to show how important it is to have a rigorous backup strategy. If I'd had to go to the Genius bar it would have cost me another day, and the laptop could have been sent away for another week for a potentially expensive repair job (although luckily I still have 3 months left on my Apple Care warranty).

The only good thing that could have come out of a trip to Leicester Highcross Apple Store would have been to get an idea of the root cause - something I have not currently got, and probably won't ever have. But I think that would have been a long shot even for an Apple Genius.

One thing I do know. I'd much rather have to troubleshoot a Mac than a PC! At least Apple provide you with all the tools to help yourself - if you follow the advice from folks in the Apple community... and continue to read the Apple Harvest blog!

Happy Easter!


  1. Hi Ally,

    You didn't mention which model of MacBook Air you have, but there is an Apple extended warranty replacement of the SSD on some models that included defective internal SSDs.

    If that is your problem, then no amount of reinstalling OS X is going to fix that hardware problem. You should take it in to have the SSD replaced under the Apple extended warranty.

    My wife had the same problem with her MacBook Air, and we took it in to have the SSD replaced under warranty (no cost) and it has been problem-free ever since!

    To find out if you have a covered MacBook Air, go to:
    "MacBook Air Flash Storage Drive Replacement Program"

    If it turns out that the SSD is not defective, then it is probably a corrupted directory on the SSD. If that is the case,there are two very easy options: 1) a fix, or 2) a restore. (you should not be wasting time and energy reinstalling OS X and building things back up... that takes too long, and is too frustrating)

    1) The Fix:
    If you have already created a boot disk for such emergencies, boot from it, and run the highly recommended DiskWarrior utility. DiskWarrior is much more efficient than Apple's Disk Utility, and usually fixes directories that Disk Utility can't fix. If you haven't already created a boot disk... now is the time to do it. It is very easy to do.

    2) The Restore:
    If DiskWarrior can't repair the SSD's directory, Then start reinstalling OS X... but this time DON'T install a fresh copy, but choose the option to restore your disk from your Time Machine backup. Choose a backup from just before things went wrong, so that you don't get corrupted files back. The restore takes less than a half hour, and works automatically, and you will end up with your MacBook Air the way it was before the problem occurred.

    I hope that you find this information helpful, and saves you the frustration that you have been experiencing.

    1. Thanks for reading and for your comment! It's a 2011 top spec 13" MBA (256Gb) so doesn't quality.

      Also I use TechTools Pro 7 and various other disk utilities but none have indicated any issues with the SSD or a corrupt volume directory.

      In the end my successful fix was pretty much as you suggested. In the past I've had problems restoring from Time Machine immediately after a "fatal" crash and have ended up having to reinstall OS X and then restoring as was the case here.

      Hopefully others will be able to pick up on your useful advice though!