How do I enable a TLS connection for a Domain on Exchange 2003?
Part I - Create and Manage Key Certificates
Install your SSL certificate. Exchange 2003 uses IIS 6. Following the IIS 6 guide on our knowledge base should guide you through this process if it has not already been completed.
Start the Exchange System Manager.
Expand the Exchange Server and click on Protocols.
Click on SMTP and then right-click on the SMTP Virtual Server.
Scroll down on the drop-down menu and click on Properties.
Click the Access tab, and then click Certificate to set up new key certificates to manage key certificates that are installed for the SMTP virtual server.
Part II - Set TLS encryption levels for the server
Start the Exchange System Manager.
Right-click the SMTP Virtual Server and then click Properties.
Click on the Access tab and then click on Authentication.
Check the Basic Authentication check box and then check the Requires TLS encryption check box.
Click on the OK button.
Part III (Option 1) - Enable TLS encryption for a specific remote domain
Create a new SMTP Connector.
For more information about how to create a new SMTP Connector, click the following article number to view the article in the Microsoft Knowledge Base:
You will need to create a new SMTP connector.
To enable TLS encryption, right-click the SMTP connector and then click Properties.
Click the Advanced tab.
Click on Outbound Security and then check the TLS Encryption check box.
Note: If the remote domain does not support TLS encryption, all messages are returned and an NDR is generated. For more information, click the following article number to view the article in the Microsoft Knowledge Base:
Part III - (Option 2) Enable Transport Layer Security Encryption for All Outgoing SMTP Connections
To enable TLS encryption for all outgoing SMTP connections, follow these steps:
Install an X.509 Server Certificate on the server. For more information about X.509 certificates, click the following article number to view the article in the Microsoft Knowledge Base:
Start Exchange System Manager.
Right-click the SMTP Virtual Server and then click Properties.
On the Delivery tab of the SMTP virtual server, click Outbound Security, and then click to select the TLS Encryption check box.
