Set Room Mailbox Permission

Example Poweshell Script you can use to Add Folder Permission for a Room Mailbox.

Set-ExecutionPolicy unrestricted  
$Cred = Get-Credential
$Session = New-PSSession -ConfigurationName Microsoft.Exchange -ConnectionUrl https://ps.outlook.com/powershell/ -Credential $Cred -Authentication Basic -AllowRedirection  
Import-PSSession $Session  
//Add the actual permission to the mailbox.  
Add-MailboxFolderPermission -Identity meeting-room@simego.com:\Calendar -User sean@simego.com -AccessRights Reviewer