Currently Being ModeratedAug 16, 2011 8:30 AM (in response to Adam317)
I have the same issue. Called Apple support who advise it's not their area and I need to speak to my Exchange guy.
All my devices synch ok but as you say, cannot delete or amend the entry....hmmm
Currently Being ModeratedAug 18, 2011 10:17 AM (in response to Adam317)
I have the same issue, even after OS X 10.7.1, and my network admin says that my Exchange account is correctly configured. He says that it is an issue with iCal writing to a local database (on the Mac), not a problem with Exchange communication.
This didn't fix anything for me - problem still exists and new invites that I see in Mail are not showing up in iCal. This suggests to me that maybe it IS an Exchange issue. Still seeking advice.
Currently Being ModeratedAug 19, 2011 6:02 AM (in response to Adam317)
Same with new Mac Book Air using Lion. I am a professional, and will have to switch to Google calendar if I can't rely on Apple. Hope someone has an answer. Jeffery
Currently Being ModeratedAug 31, 2011 10:08 PM (in response to Adam317)
I have the same problem and am not using Exchange. When I get invites, about half I click on give me this error and the appointment is not recorded. The problems seems to be a very buggy iCal and nothing to do with Exchange
Currently Being ModeratedSep 9, 2011 11:10 AM (in response to Adam317)
I'm having this issue as well on Lion. I'm not using exchange either, I'm only syncing iCal to me.com
Currently Being ModeratedSep 14, 2011 1:58 PM (in response to Adam317)
I am having the same problem. I am running Lion on a brand new macbook pro, and syncing my ical with my google calendar. Oftentimes when I delete an event, I get the same error, and it refuses to allow me to delete the event. I've been looking all over the internet but have yet to find a solution to my problem. I will probably call apple support. It's just frustrating!
Currently Being ModeratedSep 15, 2011 3:37 PM (in response to Adam317)
I found a solution. I trashed a file called "iCal 2011-08-18.icbu" It is described as a "backup file." I don't remember where I found it, but have had no trouble since. The system has not re-created such a file, perhaps because I am using the me.com server to keep my data at this point.
Currently Being ModeratedFeb 6, 2012 12:31 PM (in response to Adam317)
I've had this problem with one of the events on my calendar. And it was a repeating event. And it wouldn't let me set an end date. So it was set to repeating... FOREVER. Whenever I tried to add an end date or delete the event I'd get the error you're speaking of. So here's what I did.
1. I selected the calendar with the faulty event. I used File-> Export-->Export... and saved it as a file on my dekstop.
2. I DELETED the faulty calendar. Not the event (because I couldn't do that)... but the calendar that contained that event.
3. I made a new calendar (same name as the one I just deleted)
4. Use File->Import->Import... and I imported the filed I had just put on my desktop. It asked me which calendar I wanted to put the events on, so I put it on the new replacement folder I had just made.
Fixed. For now at least.
Currently Being ModeratedFeb 8, 2012 2:47 PM (in response to Adam317)
This happened to me (same error) but not with a specific event.
I had been experimenting with DavMail to try to get my work Exchange account working smoothly on iCal, so I had a CalDAV account there. This account seemed stuck, if I tried to remove it iCal would take a while and then show me the error "There was an error saving iCal data...".
So to fix this I just removed everything (literally everything) from:
I had a bunch of folders with long random name, they all contained some events and also a "Calendar Sync Changes" folder. Since my goal was to get a new calendar from Exchange anyway I didn't bother backing up. So I did this, opened iCal and was happy to see that it was completely blank and no accounts configured!
So I proceeded to add my new Exchange account so everything works perfectly now.
This was on Lion 10.7.3 by the way.
Currently Being ModeratedFeb 17, 2012 1:46 AM (in response to Adam317)
I found what causes this. When accepting a meeting request (.ics) by email, simply accept the request without changing anything on the request, ie. don't set the reminder options or change anything else. Then after the event is added go and edit the reminder options on the actual event. I've tested this with 3 .ics files this morning and each time I set a reminder "before" accepting the request I get iCal and iCloud errors. I even tried responding to an .ics request directly inside icloud.com and it does the same thing but luckily inside iCloud it actually pops up an error message with a "Send to Apple" option which I have done now but for me 100% the problem is related to changing anything on the original request prior to accepting / declining it.
Hope this helps.
Currently Being ModeratedFeb 18, 2012 10:04 AM (in response to Adam317)
I too had this issue, and I assumed it was because I was restoring a Snow Leopard backup, but that turned out not to be the case. The error for me was 100% correlated with my Birthdays calendar subscription, and unchecking the "Show Birthdays Calendar" cleared it up. I had a hunch it was because of a contact of mine; her birthday is February 29, which seems to confuse iCal and Address Book. It often resulted in the birthday field changing (e.g. I would open it up and March 16 would be the birthday, and another week it was Feb 16). I removed her birthday and then resubscribed to the birthdays calendar, and the problem has been eliminated. It's an easy birthday to remember, and I just said it is on March 1st instead so it will show up in iCal.
From the above discussion, I think there are many causes of this problem. I suspect most, (if not all), originate from a faulty event, faulty vcard, or faulty calendar.
Currently Being ModeratedNov 27, 2012 9:29 PM (in response to Adam317)
I just got this error today. Running 10.7.5. Hmmm....
Currently Being ModeratedMay 24, 2013 6:26 AM (in response to fredges)
I also just got this error on 10.8.3. I sync via iCloud on my iPhone 4s and my Mid-2012 MacBook Pro. Last week I went through a long process with AppleCare to fix a syncing issue, and today I got this error after I thought we had everything working right again.
Currently Being ModeratedJul 5, 2013 5:16 AM (in response to bergonzzi)
This worked for me,
i am using iCal syncing with iCloud.