Plesk Automation :: After PPA Migration - Outgoing SMTP Submission Port Error

After migrating our existing client base from legacy Plesk 9.x servers and Expand to PPA, clients phoned in with mail sending problems. These clients are using submission port 587 because their ISPs intercept port 25.

Existing client, Outlook error message:

"None of the authentication methods supported by this client are supported by your server"

Testing with Thunderbird, error message:

"An error occurred while sending mail. The mail server responded: 5.7.0 Must issue a STARTTLS command first. Please verify that your email address is correct in your Mail preferences and try again."

It seems a "fresh" PPA requires STARTTLS on e-mail clients. It is furthermore confirmed that Thunderbird detects the e-mail server settings as dependant on TLS.

The problem is that TLS doesn't seem to work properly by default.

In order to preserve our existing customer base, we follow: [URL] ....

Bottom line, in your /etc/postfix/master.cf, change the line that says "submission" from this:

submission inet n – - – - smtpd -o smtpd_enforce_tls=yes -o smtpd_tls_security_level=encyrpt -o smtpd_sasl_auth_enable=yes -o smtpd_client_restrictions=permit_sasl_authenticate d,reject -o smtpd_sender_restrictions= -o smtpd_proxy_filter=127.$

to this:
submission inet n – - – - smtpd -o smtpd_enforce_tls=no -o smtpd_tls_security_level=may -o smtpd_sasl_auth_enable=yes -o smtpd_client_restrictions=permit_sasl_authenticate d,reject -o smtpd_sender_restrictions= -o smtpd_proxy_filter=127.$

then do:
/etc/init.d/postfix reload

This is just a quick fix to get you going and stop the phones from ringing. Ideally we would like to re-enable TLS and have information as to why it is not working.