I can't use authentication of smtp! I followed the Perfect Server Guild, all working great... I can send emails em receive, but I can't use an external software (like thunderbird) to send emails! I don't receive any mail error log! I already tried to test smtp auth connection using "testsaslauthd -s smtp -u email -p password", but receive "0: NO "authentication failure". add it in /etc/default/saslauthd Code: START=yes OPTIONS="-c -m /var/spool/postfix/var/run/saslauthd" add it in /etc/postfix/main.cf Code: smtpd_tls_auth_only = yes smtpd_sasl_auth_enable = yes broken_sasl_auth_clients = yes smtpd_sasl_authenticated_header = yes smtpd_sasl_type = dovecot smtpd_sasl_path = private/auth smtpd_sasl_security_options = noanonymous, noplaintext smtpd_sasl_tls_security_options = noanonymous smtpd_recipient_restrictions = permit_mynetworks, permit_sasl_authenticated, reject_unauth_destination, reject_invalid_hostname, reject_unauth_pipelining, reject_non_fqdn_sender, reject_unknown_sender_domain, reject_non_fqdn_recipient, reject_unknown_recipient_domain, reject_rbl_client sbl.spamhaus.org, permit telnet localhost 25 Code: Trying 127.0.0.1... Connected to localhost. Escape character is '^]'. 220 <MY HOST HERE> ESMTP Postfix (Ubuntu) ehlo localhost 250-<MY HOST HERE> 250-PIPELINING 250-SIZE 10240000 250-VRFY 250-ETRN 250-STARTTLS 250-AUTH PLAIN LOGIN 250-AUTH=PLAIN LOGIN 250-ENHANCEDSTATUSCODES 250-8BITMIME 250 DSN Ubuntu 12.04 I searched many times in google, forums, etc. No result. Please, help me!