Unable to Relay emails to External domains (Exchange SMTP Relay) MxClourPro 4 years ago When you try to relay emails Internal email works fine however unable to send emails to external domains. Error: Solution: Get-ReceiveConnector “ServerCAS01\App Connector” | Add-ADPermission -User ‘NT AUTHORITY\Anonymous Logon’ -ExtendedRights MS-Exch-SMTP-Accept-Any-Recipient After the change: