We have a hybrid Exchange setup. In our on premise Exchange console (Exchange 2016), we see an error on a room mailbox:
While we don't see them in Exchange Online. And we created the mailbox in our on-prem environment.
If I click the error message, 4 more errors appear but doesn't seem relevant. The room mailbox is working fine in Exchange Online and they seem to have the right attributes. Neither does it have strange characters as the last error suggests.
Any idea's what I could check?