Enable local relay on a Microsoft Exchange 2007 Server

We have an application that sends email by relaying through an SMTP server and unfortunately its quite basic and so you cannot specify any logon credentials. Therefore I needed to allow the application to relay through a locally running Microsoft Exchange Server. This was the first time I've used Microsoft Exchange 2007, but I thought this should be easy as I knew how to do it on Microsoft Exchange 2003. How wrong was I! This is when working in IT becomes really frustrating, when things appear to be changed just for the sake of it with no apparent improvement in functionality. An hour or so later I had the solution, which was alot more long winded than I was expecting.

First open the Exchange Management Console, expand server configuration and click on hub transport. On the right hand side click New Receive Connector and a New SMTP Receive Connector wizard will open. Give the connector a name and leave Select the intended use for this Receive Connector set to Custom. If the server is multi-homed set the next page so the connector is only listening on the LAN adapter. The next part is important because you want to restrict relaying as much as possible. In this case it is a single IP address so the Start and End IP address will be the same. 127.0.0.1 didn't appear to work for me, so I used the LAN IP address of the server. Click Next and then New to create the new connector.

We now need to configure authentication parameters for this connector. Highlight the newly created connector and click on properties. Leave the Authentication Tab at defaults (Transport Layer Security Ticked) and the click on the permission group tab and ensure only Anonymous users is ticked.

Anonymous users are not granted the relay permission by default. Run the following command in the Exchange Shell but replace *NAME* with the name of the Receive Connector created earlier.

Get-ReceiveConnector "*NAME*" | Add-ADPermission -User "NT AUTHORITY\ANONYMOUS LOGON" -ExtendedRights "ms-Exch-SMTP-Accept-Any-Recipient"

Thats it, you should now be able to relay locally, which you can test using telnet. When Server applications are supposed to be moving forward I find it absolutely incomprehensible that an Admin needs to go through this process to configure relaying.

Regards