Exchange and SMTPS

Exchange with SSL certificate setup for SMTP still handles both SMTP and SMTPS on port 25. So for any mail client which expects SMTP and SMTPS to be on different ports, just forward port 465 to port 25 in your firewall. And while you are at it, forward port 587 to port 25 as well — secondary SMTP for ISP’s that block 25.

Leave a Reply

Your email address will not be published. Required fields are marked *