It is possible to configure outbound emails leaving the MailEssentials machine to go out on port 26. You will need to configure IIS SMTP server to do so. Here is the procedure to set this up:
- Go to Start > Programs > Administrative Tools > Internet Services Manager.
- In the Internet Information Services console tree (left pane), click the server that contains the SMTP virtual server that you want to configure, and then expand the server node by clicking the plus sign (+) next to the server name.
- Right-click the SMTP virtual server that you want to configure, and then click Properties.
- In the SMTP Virtual Server property sheet, under Delivery, click Outbound connections.
- In the TCP Port: type the port to be used by the SMTP server for outgoing connections (26).
- If you need to configure a smarthost for the outbound email to pass through, click on the Advanced button under the Delivery tab and configure the correspondent settings.