We have a 3 server Exchange 2013 DAG with 4 DB's, Recently one of our departments decided to change their domain name. I have been moving their linked accounts from the old domain to the new domain. We have been experiencing a weird issue with public folders and shared mailboxes.
Basically a few times a day all of the public calendars for the users seem to go offline they are unable to reconnect them and it clears them out of their favorites. I have attempted re-creating the calendars and re assigning permissions. Deleting user mailboxes and recreating them and the issue persists. After 5 to 10 minutes they can close and re-open outlook and their calendars are back but their favorites are cleared so they have to re-add the calendars.