For SMTP configuration of your email client, please use one of the following ports:
Default Ports
Port 25
Port 26
SSL Ports
Port 587
Notes
Some ISPs block port 25 as an anti-spam policy.
Port 587 is utilizing a self-signed SSL certificate. You will most likely receive an SSL/encryption warning from your email client for the first time. Do not be alarmed. Simply accept or add an exception for the SSL certificate in your email client.