Printers, scanners, and internal applications often need to send email through Exchange without authenticating. In Exchange 2010 you can allow this safely by creating a dedicated receive connector that accepts anonymous mail only from your internal network.
1. Create a New Receive Connector
Open the Exchange Management Console, go to Server Configuration → Hub Transport, and click New Receive Connector. Fill in a descriptive name and the network settings.
2. Allow Anonymous Users
On the connector’s Permission Groups, make sure Anonymous users is checked.
3. Restrict It to Your Local Network
Limit the remote IP ranges so only your internal network can use this connector. This keeps your Exchange server from becoming an open relay.
