I've been troubleshooting a problem for about a week now were one of our customers intermittently experience problems regarding booking and/or editing room calendar bookings.
Quick explanation of the setup (I did not set this up so don't blame me for how ugly this is :P ):
- Exchange 2013 2-DAG cluster
- 8 Room mailboxes
- User 1
- User 2
- Shared Mailbox 1 (Reception1)
- Shared Mailbox 2 (Reception2)
User 1 and 2 have full access to all rooms and the respective calendars, they also have full access to the shared mailboxes (Reception1 and Reception2). The shared mailboxes have full access to all rooms and the respective calendars. A few times each week User 1 and User 2 get errors when booking or editing calendar items pointing at permission issues, both with their user accounts and with the shared mailbox accounts. They get the following error message in Outlook (translated to English):
"You do not have permission to create a post in this folder. Right-click on the folder and control your permissions by clicking on Properties. Contact the owner of the folder or the administrator and ask to have your permission changed."
I have checked the event logs on both Exchange servers at the time they get the error message but no event is logged.
I have checked the Global Throttling Policy on the Exchange server, RcaMaxConcurrency is set to 40 which I believe should be enough - right? What are the possible downsides to increasing this value?
Is there any other value in the throttling policy that I should have a look at?
Any help would be appreciated!