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Opening Up Ports
To use James as your mail server, you need to open up some TCP ports. By default, the SMTP port that needs to be opened is port 25. Also, a port must be opened for the POP3 protocol. (By default, this is port 110). As you will see later in this article, you can also remotely administer James by using the Remote Manager Service. (By default, this service listens on port 4555.)