If you’re using Exchange Online today, chances are that you didn’t start out Online. Like me, you probably started with an on-premises Exchange organization and migrated to Office 365 later.

It’s been a few years since we moved from Exchange 2016 to Exchange Online, but I still have a large number of resource mailbox accounts that are homed in our on-prem Active Directory and synced to the cloud. Of course, I could just delete the old accounts and mailboxes and recreated them wholly in the cloud, but end users really like continuity. It was (and still is) just simpler for everyone this way.

But now we have Microsoft Teams and all those cool gadgets for turning conference rooms into Team-enabled meeting spaces with all of the collaboration benefits that come with it. So we needed to convert our existing Room mailboxes to Teams Rooms.

Here’s the process I used to enable a room mailbox for Teams integration. Most of this applies just as well to online-only Rooms. I’ll try to note where the instructions might differ.

If your room account is synced to Office 365 from an on-prem AD:

1. Set the room account’s password in on-prem Active Directory and set it to never expire. You can do this using ADUC, ADAC, or PowerShell.
   1. PS C:> Set-ADAccountPassword -Identity <ResourceUserName> -NewPassword (ConvertTo-SecureString -AsPlainText “<ComplexPassword>” -Force)
   2. PS C:> Set-ADUser -Identity <ResourceUserName> -PasswordNeverExpires $True
2. Enable the room account using ADUC, ADAC, or PowerShell.
   1. PS C:> Enable-ADAccount –Identity <ResourceUserName>
3. Wait for these changes to replicate up to Office 365. When the account shows that sign-in is unblocked, you’re ready to proceed.
4. Assign an Office 365 license to the room account with at least Exchange, Skype for Business, Sharepoint, and Microsoft Teams. (There is a special license available for this purpose, but as long as you have these 3 components available, you don’t need it.)

Steps for both online-only and on-prem accounts:

1. Connect to Exchange Online PowerShell.
   1. PS C:> $MyUpn = <YourAdminUserPrincipalName>
   2. PS C:> $UserCredential = Get-Credential -Credential $MyUpn
   3. PS C:> $ExchangeSession = New-PSSession -ConfigurationName Microsoft.Exchange -ConnectionUri https://outlook.office365.com/powershell-liveid/ -Credential $UserCredential -Authentication Basic -AllowRedirection
   4. PS C:> Import-PSSession $ExchangeSession
2. Make sure the Room Mailbox account is enabled for logon in Exchange. Use the same password you did for the on-prem account.
   1. PS C:> Set-Mailbox -Identity <RoomUPN, Alias, or EmailAddress> -EnableRoomMailboxAccount $true -RoomMailboxPassword (ConvertTo-SecureString -AsPlainText “<ComplexPassword>” -Force)
3. Run these cmdlets to connect to Skype PowerShell and enable the meeting room for Skype. This assumes you already ran the cmdlets for Exchange and you have the SkypeOnlineConnector module installed on your computer:
   1. PS C:> Import-Module SkypeOnlineConnector
   2. PS C:> $SkypeSession = New-CSOnlineSession -Credential $UserCredential
   3. PS C:> Import-PSSession $SkypeSession
   4. PS C:> Enable-CsMeetingRoom -Identity <RoomUPN> -SipAddressType UserPrincipalName -RegistrarPool (Get-CsOnlineUser -Identity $MyUpn).RegistrarPool

Now wait 24 hours and then test the account by logging into Teams. If it doesn’t work right away, don’t stress about it yet. I have had to wait at least 24 hours every time.

P.S. Copying and pasting code into WordPress often produces unintended results. Please let me know if you spot an error!