Last time, I killed my mum's Mac on Christmas day.
I was a little late this time. It took me until yesterday.
Well, technically Anne did it this time, but only by doing the same thing I did two years ago, which is exactly what I would have done if I'd been the one sitting in front of the computer, because I had forgotten what happened last time.
Heck, I wasn't sure what even caused the problem last time. Only now that it's happened twice do I have some degree of confidence about it.
Word to the wise: If your mum's got an eMac with OS X Tiger on it, and she's just clicked the cancel button every time the computer said there was an update it'd like to install, and you eventually sit down in front of the computer and say "yes" to the literal years of updates that're all waiting to be installed... then that eMac will go horribly wrong.
Perhaps the updates would have installed OK if we'd done absolutely nothing with the computer while they were installing. Including just clicking the "stop" button on the updater so we could make a backup first, which ironically seems to be what touched the problem off this time.
(Apparently the current version of OS X shuts everything down before it updates. I suspect there may be a connection between this problem and that feature.)
The computer looked, at least, less broken this time. No scary boot-up screen colours, just a power-on to usable-desktop time of about 30 minutes. But it still wasn't fixable on site.
(Which xkcd comic was it that showed the traditional "solving a computer problem" flow of activity? [UPDATE: Naturally, a reader found it for me almost instantly.] You know - you start out working on the problem, then trying to solve the problems your attempt to solve the problem caused, then just trying to get it back the way it was, then admitting that the fire has claimed the house but you think you might still be able to save the garage...)
So I'll be visiting Mum again later today. Provided the gigaton of updates currently trickling into the reinstalled OS don't pole-axe it again, of course.