Many ISPs and firewall configurations now block outgoing mail / SMTP connections on port 25 (the default port for SMTP) - This can be due to the ISP wanting to limit malicious activity on their networks such as users sending SPAM or large volumes of unwanted email.
Raines Internet Solutions offers connectivity to our SMTP server on an alternative port number to workaround these restrictions. You can reach your domain name's SMTP server (e.g. mail.domain.com.au) on either Port 25 or 587. Please remember that regardless of which port you decided to connect on, both require authentication. We do not operate open-relay on our email servers and we require all users to identify themselves before sending email through our systems.
This port change workaround applies to both our Linux and Windows shared-hosting platforms.
Check the documentation for your preferred email client on how to change the default SMTP port. If in doubt, log a support request if you have any questions with regards to changing the default SMTP port in your email client.