Why do I get a '"Calendar Cache" couldn't be moved' error when launching Calendar?

Question

After upgrading to Mountain Lion, I get the following error message when I launch Calendar.app:

"Calendar Cache couldn't be moved because you don't have permission to access "Calendars".

When I click "OK", Calendar quits.

This user is an administrator on the machine. I tried granting the user 'Read & Write' access to Calendar.app, but nothing changed.

I have another administrator account on the same machine that can launch Calendar.app without issue.

Answer 1

If repairing permissions with Disk Utility and/or checking permissions for the actual calendar-files in /Users/<username>/Library/Calendars do not work maybe this will:

https://discussions.apple.com/thread/3773022?start=0&tstart=0

Seems a bit drastic though. I have not tried this myself. I suggest having a backup just in case.

Update: I just tried the instructions from the thread at apple discussions, and everything on my 10.8 system is OK. It's kind of a supercharged permissions-repair (lacking better terms atm).

If it works, thank macjack at the appe forums. If not, tell me :)

On my mac the ~/Library/Calendars/Calendar Cache is owned by me:
-rw-r--r--@ 1 nils staff 2813952 Jul 31 18:44 Calendar Cache

It may be of help if you post the output from this terminal command:
ls -lar ~/Library/Calendars/|grep "Calendar Cache"

Answer 2

Since I've never actually used iCal/Calendar.app on that user account before and there was no data to potentially lose, I decided to try deleting ~/Library/Calendars/Calendar Cache entirely. Calendar.app started without complaint after that.

I'm not sure what would have happened to my calendars if I actually had anything in Calendar.app to lose, but it did fix the issue.