Postfix Error - Relay Access Denied

Hey guys, i’m kinda new to the virtualmin environment, and i’ve run into this problem with Postfix where I can receive e-mail fine… but I can’t seem to send any mail… I’m using Windows Mail… and everytime i try to send an email i get this error message…

The message could not be sent. The authentication setting might not be correct for your outgoing e-mail [SMTP] server. For help solving this problem, go to Help, search for “Troubleshoot Windows Mail”, and read the “I’m having problems sending e-mail” section. If you need help determining the proper server settings, please contact your e-mail service provider.

The rejected e-mail address was ‘’. Subject ‘Re: TEST feb 19’, Account: ‘’, Server: ‘’, Protocol: SMTP, Server Response: ‘554 5.7.1 Relay access denied’, Port: 25, Secure(SSL): Yes, Server Error: 554, Error Number: 0x800CCC79

My Postfix is as follows

See /usr/share/postfix/ for a commented, more complete version

Debian specific: Specifying a file name will cause the first

line of that file to be used as the name. The Debian default

is /etc/mailname.

#myorigin = /etc/mailname

smtpd_banner = $myhostname ESMTP $mail_name (Ubuntu)
biff = no

appending .domain is the MUA’s job.

append_dot_mydomain = no

Uncomment the next line to generate “delayed mail” warnings

#delay_warning_time = 4h

readme_directory = no

TLS parameters

smtpd_tls_cert_file = /etc/ssl/certs/ssl-cert-snakeoil.pem
smtpd_tls_key_file = /etc/ssl/private/ssl-cert-snakeoil.key
smtpd_tls_session_cache_database = btree:${data_directory}/smtpd_scache
smtp_tls_session_cache_database = btree:${data_directory}/smtp_scache

See /usr/share/doc/postfix/TLS_README.gz in the postfix-doc package for

information on enabling SSL in the smtp client.

alias_maps = hash:/etc/aliases
alias_database = hash:/etc/aliases
myorigin = /etc/mailname
mydestination =,,,localhost,
mailbox_size_limit = 0
recipient_delimiter = +
virtual_alias_maps = hash:/etc/postfix/virtual
sender_bcc_maps = hash:/etc/postfix/bcc
mailbox_command = /usr/bin/procmail-wrapper -o -a $DOMAIN -d $LOGNAME
home_mailbox = Maildir/
smtpd_sasl_auth_enable = yes
broken_sasl_auth_clients = yes
smtpd_recipient_restrictions = permit_mynetworks permit_sasl_authenticated reject_unauth_destination
myhostname =
mynetworks = [::ffff:]/104 [::1]/128

Any help would be greatly appreciated !!

Rick “ckoi”


You’ll want to take a peek in the error logs, either /var/log/maillog or /var/log/mail.log, to see what errors are showing up in there.

But, I’d make extra-sure of these two things:

  1. That your email client is setup to do authentication with outgoing emails – many don’t by default

  2. That you are using the correct username and password for that authentication

However, even with those two items, I’d suggesting looking in the mail log for additional clues.