I recently made the switch from Windows to Mac. Don't panic, I still use bootcamp to boot into Windows regularly for development work, but I'm really making an effort to "be a Mac," at least for a little while.

I just tried to add my Google Calendar as a caldav calendar. My first issue was that you can't use the "Automatic" account type, or even the "Google" account type, you should follow the instructions very carefully on the google calendar help page. Once I followed the instructions carefully my calendar seemed to start to sync.

I use Google Calendar quite a bit, so I'm sure there were quite a few items in there, but after about a minute I became impatient and closed iCal. When I restarted it all my calendars were gone, imagine my surprise :)

I started digging around on the internet, but found nothing that addressed my specific issue. Many crashing iCal issues, but nothing that mentioned iCal simply deleting or not loading the calendars that were there.

I deleted the iCal preferences files found in my ~library/Preferences/ directory (anything that starts with com.apple.iCal) but that didn't help.

The final solution was to go to ~Library/Calendars and move the newly added google calendar to the trash. It seems this got corrupted when it was trying to pull down the data from Google. Once the file was corrupted iCal simply stopped loading any calendars, and displayed a completely blank calendar.

Of course if I were going to recommend a solution to Apple, I would say to alert the user of the corrupted file, ask them if they'd like to keep or delete the file and where it lives on the disk, then (gasp) continue loading all uncorrupted calendars.

Joe