Mac OS X Update Fix if Interrupted and Can No Longer Boot
In some cases people are able to reboot their computers just fine, but some are unable to boot back into the Mac OS. My problem occurred when my Mac was in the middle of installing the the 10.5.6 update. I stupidly powered down in the middle of the update thinking the bar was frozen. Upon trying to boot up in the Mac OS again the Apple logo and the spinning grey progress ball would appear but then the screen would go dark grey and a message would appear (in four languages) that I needed to restart my computer. I read online that this is called a 'kernel panic.' This cycle would continue indefinitely. (It should be noted at this point that I also had a Windows partition installed. I was able to hold down the 'option' key upon start up and choose to boot into Windows with no problems at all.)
With a failure to boot into the Mac OS I turned first to the Mac OS discs that had been included with my computer. I used all of the tools included in the Disc Utility with no success. I did not want to resort to having to install a fresh copy of the OS. I even tried using the program called 'Disc Warrior' to repair the directory. This can be a very useful program in rescuing drives that have crashed and seem to be no longer accessible. It did not help me in this case. The kernel panic message remained ever time I tried to boot up in the Mac OS.
Then I had an idea. Why not find an external hard drive with Mac OS X installed on it and boot from that? Lacking a dedicated external drive I turned to my trusty 60GB ipod classic. I connected it through USB to my Mac and booted up with the OS discs. From there I formatted the ipod to the proper specifications needed to install Mac OS X. After formatting, it allowed me to install a clean copy of the Mac OS onto the ipod, I was able to hold down the option key and choose to boot from the ipod. Upon successful boot-up I had two choices A)Grab all my files that I needed then reinstall a fresh copy of the Mac OS on my internal drive or B) Try and reapply the Mac OS X 10.5.6 update using the standalone installer I had downloaded from Apple just for this occasion. I chose the latter. To my amazement and joy all I had to do was plug in my flash drive in the other USB part containing the update and choose to install it to my internal drive. It went off without a hitch and after a successful reapplication of the update I restarted and booted from my originally inaccessible Mac OS partition on my internal drive.
I hope this helps someone out there.
- AV
Macbook Pro, Mac OS X (10.5.6)