Kernel Panics Can Seriously Damage Your Health

They say that getting married, moving house, starting a new job and bereavement are the most stressful things that happen to us in our lives. Well, they need to add installing a new or upgraded operating system to the list.

Having successfully installed OS X 10.8.5 on the MacBook Air while having breakfast this morning, I retired to the Apple Harvest office to repeat the process on the new iMac. I should add that both installations were being done through the Mac App Store - no magic tricks required for a routine software update. The OS asked for a restart as usual and when it had rebooted it went straight back into 10.8.4; on the MBA it went to a modeless dialogue box and showed the download progress.

I tried again, and this time I got the expected behaviour. The download proceeded without any problems but when it rebooted I got a multi language message saying something like "the computer had previously closed down because of an error. Wait a few seconds or press any key to continue". I pressed any key and the system went into kernel panic and rebooted into a continuous cycle.

I powered down, waited and restarted. Same thing. I tried to reboot from a different disk (holding down the Alt key) and was surprised to only see the main disk (no recovery disk nor any of the three external drives. Same problem on selecting the drive. I tried safe mode (holding down the Shift key) but it never even made it through the boot sequence. I tried diagnostic mode (holding down the D key) and that appeared to crash after 30 seconds. I was beginning to have my own kernel panic by now.

Not my actual system but you get the idea!

I tried resetting the PRAM (Cmd+Alt+P+R which requires considerable manual dexterity when you've only got little fingers like mine!). A glimmer of light. A new screen came up that I'd never seen before saying "attempting internal recovery" and then a little globe appeared with a progress bar underneath. This ran to completion, rebooted and the same error message appeared briefly before going into the Utilities app. Phew, I thought, at least the machine itself doesn't appear to be kaput.  My worst thought that the 3Tb Fusion drive was corrupt proved to be over-reaction.

I elected to reinstall the OS and after the longest hour of this year, finally everything is back to normal. My heart rate slowly went back to normal and then I noticed the date…Friday 13th September!