Hi @Roger Roger
I tested in my lab and was able to reproduce the issue.
I suppose that it should be the expected behavior.
The room mailbox is listed under mailboxes instead of resources because its RecipientType is MailUser.
It is also mentioned in this link:
New-RemoteMailbox
If you run the following command via EMS:
Get-ADuser -Identity room1 -Properties * | fl msExchRemoteRecipientType,msExchRecipientDisplayType,msExchRecipientTypeDetails
You may see the results match the ones in this link:
Recipient Type Values
33 ProvisionMailbox, RoomMailbox
-2147481850 MailUser (RemoteRoomMailbox)
8589934592 RemoteRoomMailbox
And it shows the correct values of the remote mailbox.
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