I had a similar problem when I turned on calendar synching to iCloud and then later deleted the calendars in iCloud. After that, every time I applied a backup of may calendars in iCal (also using .icbu file), they disappeared in iCal after turning on internet access. The backup file somehow contained the information that the calendars where using iCloud synch, as every time in iCal in the menu 'iCal', 'Preferences...', 'Accounts' there was again my iCloud account even if I deleted it before applying the backup.
Here is what I did to solve this for me, maybe this can give you some hints and help you:
- create a backup of all iCal data by using the menu 'File', 'Export', 'iCal Archive...'
- delete all calendars in iCloud (using website icloud.com)
- disable iCloud calendar synch in 'System Preferences', 'iCloud', uncheck 'Calendars' and let it delete all calendars on your Mac
- turn off internet access on your computer
- apply created backup of .icbu file in iCal (menu 'File', 'Import', 'Import...')
- (my calendars appeared again in iCal but all had the type 'iCloud' calendar)
- export every iCloud type calendar individually (right click on the calendar in the calendar list popup and use 'Export...' giving you a .ics file for every calendar)
- delete all iCloud type calendars in iCal
- recreate all calendars in iCal (menu 'File', 'New Calendar') but make sure the type of the calendar is 'On My Mac'
- import calendar data for every calendar by using the menu 'File', 'Import', 'Import...' and then selecting the previously exported .ics file; select the destination calendar the .ics file belonges to
- create again a backup of all iCal data by using the menu 'File', 'Export', 'iCal Archive...'
- turn on internet access on your computer
Now I had all my calendars again, but I did NOT turn on iCloud calendar synch again, as I didn't dare to try it again. If you like you can go on here and try it ;-)
Regards and good luck
I have no words to thank you for the precise instructions! I was able to get all my calendars back! You literally saved my year!
I found a way of sending the events back to iCloud without erasing everything on my iCal here. Hope this is of some help.
Thank you Michael,
I really did not want to use Icloud for Contacts etc, When I discovered Maverick did not allow direct sync from Mac to Iphone. I thought I would experiment with Ical (less critical - personally) only to discover it was a one way street. Now, a couple of hours later I am more or less back where I was.
I guess from now on I will be doing updates to contacts on both the Mac and the Iphone.
I wonder whose bright idea that was?