The installer will now test the TCP/IP ports, including the SMTP, ETRN, and WWW ports that are needed by SLmail for Web-based Remote Administration. A summary will appear, as illustrated below.
SLmail Installation Port Test dialog box
During the port test, SLmail will determine which TCP/IP ports are available for its use. If a port is in use by another application or service, SLmail will label the specific port as being in conflict. If there is a conflict, selecting Advanced will allow you to manually assign a different port number.
Note: Seattle Lab recommends that Port 25 always be used for the SMTP Port.