Hello
Setting up the Sophos MTA to use ISP email server as a relay for the email.
I configure the smarthost using the ISP email server.
I tick the authentication box, add in the username and password for SMTP Authentication.
The Sophos cannot forward emails, they are listed as failed.
I have the same setup in Outlook on my desktop PC, so I can validate the username and password, and am using Port 25 SMTP.