Update to 10.5.5 failed

Question

I tried to update to OS 10.5.5 and the update failed. The computer would no longer boot- hang on the apple symbol.
I have reinstalled 10.5.2 and updated the computer to 10.5.4 successfully and I can get it to boot once again. However, the computer will no longer properly shut down. When I select shutdown the video goes blank and the power LED on the mini goes out but I can hear something still operating inside (could be hard drive spinning). I feel heat coming out the back of the computer as well, even after 15-20 minutes.
When I try to restart the machine will not restart. It just sits there.
If I hold down the power button the computer will eventually shut off completely- no more noise and heat. After this complete shutdown the computer can then be restarted normally but it does indicate that a kernel panic occurred.
This sounds like a firmware problem to me- system doesn't respond properly to shut down. I attempted to use the firmware updater download but it tells me that the firmware does not need updating and refuses to run. Firmware version reports as 1.19f2.
Anyone have an idea how to fix this? Not a tragic problem but very annoying and obviously something broke when the update failed.

Answer 1

If the other system you have is an identical Mac, the easiest way to clone your good one to the problem mini is to connect the two together with a firewire cable, then put the problem system into Firewire Target Disk mode by holding the T key down during booting. With the other mac running, you should then see the problem system's hard drive appear on the desktop of the good one. Download a copy of SuperDuper! from www.shirtpocket.com on the good system and set it to do a complete clone, with the good drive as the origin and the 'bad' drive as the target.
Another way to do it is to reinstall MacOS on this mini, then (again) connect the two with a firewire cable, but this time put the other one into firewire target disk mode so that it can be 'seen' by the newly installed one. As you then go through the initial setup after the install, the Migration Assistant will ask if you want to migrate data, settings and applications from another system or volume. Click volume, which will then allow you to select what you want to migrate from the remote Mac. Beware that you shouldn't use this option to move applications unless both systems are either Intel or PPC.
It must be said though that your objective of saving time in the reinstall is to some degree in conflict with the objective of best reliability. The better way - from the standpoint of completing an effective reinstall with the least risk of problems - is to do it the hard way by reinstalling MacOS and your applications, and then manually recreating the accounts and moving your data back. Shortcutting this may save time and prove more convenient, but reduces the level of confidence that the result will be optimal. Personally, I'd do it the manual way but I know that's easy for me to say when I'm not having to spend the time to do it! If the systems are the same, the next best option would be to erase and install on the mini, then use the Migration Assistant with the two systems connected via FW.