We have an issue that we cannot connect to any shared calendars or mailboxes. I have given myself full permissions to the mailbox and when I add it to my Outlook I get a message that states:
The set of folders cannot be opened. Microsoft Exchange is not available. Either there are network problems or the Exchange server is down for maintenance
If I try connect to the test users calendar then I get a message that it is read only.
For this user I gave myself full access to the mailbox for testing an issue where we have shared calendars under user accounts and they are no longer accessible for any of our users