iCal ate my Calendars

Actually, it's not quite as bad as it sounds. "Calendars" are what any sane program would call "categories", or something similar—essentially just labels to group events (and tasks). And iCal didn't destroy them, it just stopped showing them to me in the "calendars" list pane. This is how it happened this afternoon:

• I opened iCal. The list of calendars was blank. There were no events in my week-view. In other words, my calendar looked pretty much blank, and I was concerned. I sync my Palm TX pretty regularly, so there were no tears yet.
• Progressing to the next level of problem solving (pressing every available button), I swapped to the month view. My events were now visible. I switched back to the week view, and they were visible there too. It looked like the data was intact (good), but the GUI was misbehaving (bad). There were still no calendars in the list.

My most recent iCal backup was about a month old, and I made another one. And then I hit Google.

The Apple forums were semi-helpful: at least they confirmed there were a handful of others seeing a similar problem, and all recently as far as I could tell. Sadly, there were no useful answers. (Not everyone has a spare Mac, or a .Mac account, so I had to skip over those pseudo-solutions, none of which adequately explained the problem anyway.) I tried the usual Mac contortions like deleting (well, moving elsewhere) the iCal preference files, and, yes Dale, even emptying the Trash. Nothing worked.

A helpful guy (could have been a girl I suppose, "Angry Ant") on the #macosx channel on IRC helped me with what he thought might be a workaround. I moved the entire ~/Library/Application Support/iCal folder to the Desktop (that is, effectively deleting it, but keeping it in case I needed to restore it), and then started iCal. It fired up in pretty much the default state: no events, and just the "Home" and "Work" default calendars. Then something really weird happened: without doing anything, about 10 seconds later, all my events and calendars just reappeared. Magic. (I suspect it was reloaded from Sync Services, but I don't know enough about how all that works to be sure.) There were three problems:

1. My colour scheme for the calendars was gone. Small deal.
2. My calendar groups (think "parent categories") were gone. Medium deal—I wanted to reorganise anyway.
3. The size on disk of the contents of the folder I moved out was 2.4M ("du -h ." in the top-level directory for Unix nerds following along), the size of the folder regenerated in its place was 1.8M. Potentially fairly large deal. Where was the rest of the data?

Anyway, I eyeballed a few months worth of events, and couldn't see any holes. It seemed to be intact. I re-organised my calendars, synced with the Palm a couple of times, and as far as I can tell I am back where I started, and better organised. Still, it's about two hours of my life I'll never get back. Thanks iCal.

iCal