- | Exchange Management Console - Server Configuration - Hub Transport - New Receive Connector |
- | Give it a name i.e. "Open Relay" and leave "Custom" selected - Next |
- | Bind it to "All available IP Addresses on Server" through port 25 (assuming this is what you want) |
- | Enter your FQDN this server should announce itself as - Next |
- | Remove the default specified remote IP address range and enter in the specific or range of IPs you intend to allow to relay through this host - Next |
- | Complete the creation of the new receive connector and then edit the properties of the new connector |
- | Goto the "Authentication" tab and uncheck everything except "Transport Layer Security (TLS)" |
- | Next goto the "Permissions Groups" tab and uncheck everything except "Anonymous users" - click "Apply" and then "Ok" |
- | Now we need to edit the connector through the following shell command to enable it for open relay: |
| o | Get-ReceiveConnector "Open Relay" | Add-ADPermission -User "NT AUTHORITY\ANONYMOUS LOGON" -ExtendedRights "ms-Exch-SMTP-Accept-Any-Recipient" |
|