15
Feb
SMTP Port 25 * Access Denied! *
Over the last few months we have had an increasing number of support calls that relate to failing SMTP connections over Internet connections.
This can happen on a range of network connections, whether it's mobile devices on 3G or home users trying to access their MDaemon mail server. Even businesses can find that they can no longer create outbound SMTP sessions on port 25 on their office broadband connections.
One of the more common customers support calls i get relates to MDaemon suddenly sending vast amounts of spam email. This floods the outbound Internet connection and everything crawls to a halt.
Secondary to this the server's public IP address can get listed on various external SMTP blacklists which the customer then has to request removal from.