Currently Being ModeratedNov 1, 2011 9:32 AM (in response to ryan.j)
I got this message too after I started iCloud syncing. Just close iCal and open it back up again. That's all I did and it seems to be working fine for me.
Currently Being ModeratedNov 2, 2011 3:37 AM (in response to chemicalRXN)
That works temporarily for me, but the popup message then appears again at other times.
Currently Being ModeratedNov 2, 2011 8:29 AM (in response to ryan.j)
You can try removing the plist files. Please note this may delete certain settings you had in iCal and you will need to adjust them again. Back up your calendars, if they are stored locally (stored on your machine as opposed to Google, iCloud, etc.)
- Open Finder and hit Command+Shift+G. Here type in the following location: /Users/YourNameHere/Library/Preferences
- This will take you to the Library folder, which was hidden in Lion. There you will find about 4-6 files that have iCal in the name. (ex: com.apple.iCal.plist)
- Take these files and move them to a different folder temporarily. There should be no iCal plist files left now.
- Procede to restart you computer with the box for "reopen windows when logging back in" unchecked. After the restart, open iCal and allow a moment for iCal to rebuild it's plist files. If iCal ceases to work after this step, just replace the plist files you moved temporarily (shouldn't be an issue though, I wrote this just in case).
Theoretically, most applications can rebuild their plist files and go on without a problem. If this doesn't work, there could be an issue with a sync service that will take a much more to fix.
Let us know if this fixes the problem. Good luck!
Currently Being ModeratedDec 10, 2011 7:48 PM (in response to chemicalRXN)
this worked for me - thank you - that was son annoying every time i booted up
Currently Being ModeratedJan 12, 2013 10:21 AM (in response to chemicalRXN)
Thanks so much for this. I'd be suffering from the 'upgrading calendars' problem and this seems (fingers crossed) to have solved it. Just one question - I found 7 com.apple.iCal plist files (.Alarm.plist, .Alarm.plist.lockfile, .AlarmScheduler.plist, .helper.plist, .helper.plist.lockfile, .iCal.plist and .iCal.plist.lockfile). Only one of them has returned (com.apple.iCal.plist) but the Calendar seems fine. Do I need to add the others back in? Or should I just carry on with the one plist? If the latter, is it safe to delete the old files?
Currently Being ModeratedOct 3, 2013 7:27 AM (in response to chemicalRXN)
I can't see and iCal plist files . could that be the issue?