Issue: You want to copy an existing receive connector to a new receive connector. This is helpful when you need to create a new “anonymous relay connector” and want to avoid manually entering the a long ‘IP allowed’ list, from a receive connector on a legacy Exchange server.
Solution: Create new Exchange 2013 receive connector and copy IP list from existing legacy Receive Connector using Exchange Management Shell:
New-ReceiveConnector -Name “Relay Connector MAIL2013” -Server MAIL2013 -Usage Custom -Bindings 0.0.0.0:25 -MaxMessageSize 50MB -TransportRole FrontEndTransport -RemoteIPRanges ( Get-ReceiveConnector “MAIL2010\Relay Allowed” ).RemoteIPRanges
Receive connector permissions: If you are using the new connector to allow anonymous relaying of SMTP email outside your network, you will need to apply permissions to the receive connector to allow anonymous relay outside your domain.