this helped me: https://serverfault.com/a/690658/341161

This didn’t work for me.

I am having the worst trouble trying to setup postfix/dovecot behind a Comcast residential gateway (SMTP port 25 block).

503 5.5.1 Error: authentication not enabled

Here’s some of the “/etc/postfix/master.cf”:

==========================================================================

smtp inet n - - - - smtpd #smtp inet n - - - 1 postscreen #smtpd pass - - - - - smtpd #dnsblog unix - - - - 0 dnsblog #tlsproxy unix - - - - 0 tlsproxy #submission inet n - - - - smtpd -o syslog_name=postfix/submission -o smtpd_tls_security_level=encrypt -o smtpd_sasl_auth_enable=yes

-o smtpd_reject_unlisted_recipient=no

-o smtpd_client_restrictions=$mua_client_restrictions

-o smtpd_helo_restrictions=$mua_helo_restrictions

-o smtpd_sender_restrictions=$mua_sender_restrictions

-o smtpd_recipient_restrictions=

-o smtpd_relay_restrictions=permit_sasl_authenticated,reject

-o milter_macro_daemon_name=ORIGINATING

587 inet n - - - - smtpd -o syslog_name=postfix/smtps

-o smtpd_tls_wrappermode=yes

-o smtpd_sasl_auth_enable=yes

-o smtpd_reject_unlisted_recipient=no

-o smtpd_client_restrictions=$mua_client_restrictions

-o smtpd_helo_restrictions=$mua_helo_restrictions

-o smtpd_sender_restrictions=$mua_sender_restrictions

---- Here’s some of the “/etc/postfix/main.cf” modifications made following this article (https://samhobbs.co.uk/2013/12/raspberry-pi-email-server-part-2-dovecot):

mynetworks = 127.0.0.0/8 [::ffff:127.0.0.0]/104 [::1]/128 mailbox_size_limit = 0 recipient_delimiter = + inet_interfaces = all inet_protocols = ipv4

home_mailbox = Maildir/ mailbox_command =

smtpd_recipient_restrictions = permit_sasl_authenticated, permit_mynetworks, reject_unauth_destination

smtpd_helo_required = yes smtpd_helo_restrictions = permit_mynetworks, permit_sasl_authenticated, reject_invalid_helo_hostname, reject_non_fqdn_helo_hostname, reject_unknown_helo_hostname check_helo_access hash:/etc/postfix/helo_access

smtpd_sasl_type = dovecot smtpd_sasl_path = private/auth smtpd_sasl_auth_enable = yes

– Comcast SMTP Relay

relayhost = [smtp.comcast.net]:587 smtp_sasl_auth_enable = yes smtp_sasl_password_maps = hash:/etc/postfix/smtp_passwd smtp_sasl_security_options = noanonymous smtp_sasl_tls_security_options = noanonymous

I have had the AUTH PLAIN, IMAP, and relay host working today already, but something has broken it.

Also, the messages accepted in the relay never delivered, but they were accepted by a 3rd party, Comcast, relay, which would have delivered the message even if my networking wasn’t correct, I’d assume, no?

Please advise for what you need to assist in troubleshooting.

Thanks!

This is odd. The postconf tool can also be used to configure settings in addition to just viewing them. I would try the following to attempt to change the setting:

sudo postconf -e 'smtpd_sasl_auth_enable = yes'
sudo service postfix reload

and then check if the configuration variable has changed.