Limit access to meeting rooms only

If you only want Planner to have access to view meeting rooms or if you want to limit it so that Planner cannot view specific meeting rooms, you need to create an “Application Access Policy”.

If you don’t, Planner will have access to all meeting rooms and resources by default.

Follow the instructions below:

1. Create an email-enabled security group with all meeting rooms in it.
2. Connect to Exchange Online through PowerShell
   https://learn.microsoft.com/en-us/powershell/exchange/connect-to-exchangeonline-powershell?view=exchange-ps&preserve-view=true
3. Run the following command in PowerShell:
   New-ApplicationAccessPolicy -AppId [AppID] -PolicyScopeGroupId [SecurityGroupEmail] – AccessRight RestrictAccess -Description “Restrict this app to members of distribution group” [AppId]: Application ID of the app registration that was made for the application earlier [SecurityGroupEmail]:Email of the mail-enabled security groups containing all meeting rooms.

   Note it can take over an hour before the new policy is replicated to work against
   Microsoft’s Graph API.

4. You can use the following command to verify if the application has access to a
   specific mailbox:
   Test-ApplicationAccessPolicy -Identity [Mailbox] -AppId [AppId][Mailbox]: Email of the meeting room to test access against
   [AppId]: Application ID of the app registration that was made for the application earlier