Room mailboxes and Office365

For no real reason I decided to try adding some rooms to my Office365 account. You do this from the Admin screen, select Manage under Exchange.


It should take you straight to MailBoxes for your organization but that’s where you want to end up anyway. Select new Room Mailbox



Give it a name, email address and any details you want. Lastly select how you want to accept meeting requests. This is where I hit a snag. If I selected Automatically accept or decline booking requests I got the following error when I saved.

Cannot open mailbox /o=ExchangeLabs/ou=Exchange Administrative Group

(FYDIBOHF23SPDLT)/cn=Configuration/cn=Servers/cn=SN2PRD0610MB371/cn=Microsoft System Attendant

I ended up figuring out that if you save the room using the delegate option you can go back in and change it after. I had the issue for 2 more rooms and then it finally went away.

Finally I wanted to change the room so it shows details of the meeting that’s booked the resource like the organizer & meeting subject. To do this you’ll have to crack open Powershell.

I found this info on this blog.

If this is the first time you’ve used Powershell you’ll have to change the ExecutePolicy to allow RemoteSigned.

Open Powershell (run as admin)

Run the cmd:


and it probably says Restricted

Run the cmd:

Set-ExecutionPolicy RemoteSigned

Get-ExecutionPolicy should now say RemoteSigned

Setup the credentials

@LiveCred = Get-Credential

A logon dialog will pop up, sign in using your Office365 credentials

$Session = New-PSSession –ConfigurationName Microsoft.Exchange-ConnectionUri –Credential $LiveCred –Authentication Basic –AllowRedirection 

It’ll come back and say the connection has been redirected.

Import-PSSession $Session

Set the Room calendar to show limited details by default

Set-MailboxFolderPermission –AccessRights LimitDetails –Identity [RoomName]:\calendar –User default
Obviously replacing [RoomName] with the Room’s mailbox name.
Set-CalendarProcessing –Identity [RoomName] –AddOrganizerToSubject $true –DeleteComments $false –DeleteSubject $false

Finally here’s a link for setting up an equipment mailbox so I could add my bbq or grill as a equipment resource rather then a room. 

Don’t forget to close the Powershell session Remove-PSSession $Session.