We have an assistant that manages two VPs. The user is delegated to view and manage both VPs calendars. The assistant has no issues creating and viewing and modifying one of the VPs calendars but the other one produces an error when trying to open any item.
Cannot open this item. Cannot open free/busy information. You do not have sufficient permission to perform this operation on this object. See the folder contact or your system administrator.
The assistant can see the items it just when they try and open them for this one VP. Also she cant create any meetings within the calendar.
I have tested this by creating another new user and added them as a delegate to the VP and it works fine I can see the calendar items and modify them. I can also add the assistant as a delegate to the test user and they can see the test users calendar without issue.
The VP did have this issue before http://support.microsoft.com/kb/950794
but it has since been fixed and the assistant has been removed and added back with no luck. I have also checked the VPs and the assistants mailbox and AD permissions and cant find anything that stands out.
I am thinking the issue is with the assistants mailbox or account since I can add other users to the VPs account and it works without issue. Also the test account was copied from the assistants account to make sure group membership was the same.