So we've just finished moving all of our users to Exchange 2016 Databases. This has gone fine, except one particular user suddenly can no longer view other people's calendars. It's just this one user to our knowledge, and it doesn't matter who he tries to open, everyone's calendar says "No Connection".
I checked Outlook Connection Status - All was good, even the connections to the calendars he was trying to open
Recreated Outlook profile - same issue
Cached mode vs. no cached mode - same issue
Tried on a different machine - Same issue
Tried on a different machine with Outlook 2019 (vs 2016) - Same issue
Forced his machine to access Exchange CAS Server directly (vs through Kemp Load Balancer) - Same Issue.
The Kicker - Tried using Outlook Web Access - this WORKS!
Also, I can open his calendar no problem.
Also, he can open ROOM mailbox calendars no problem.
He can open shared mailboxes (Full mailbox contents) No problem.