Hi @Edward West ,
After my test, I think it is possible, but you need to create inbox rule in room mailbox, please use this command to grant the full access permission of the room mailbox to your account. (The purpose here is to open the room mailbox).
Add-Mailbox Permission -Identity room1 -User user1 -Access Rights Full Access -Automapping $false
1.use "outlook web app" open the room mailbox.
2.create new rules using details below.
Best regards,
Shao fan
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