>покажите postconf -n|grep sasl

broken_sasl_auth_clients = yes
lmtp_sasl_auth_enable = no
lmtp_sasl_password_maps =
lmtp_sasl_security_options =
smtpd_client_restrictions = permit_sasl_authenticated
smtpd_recipient_restrictions = check_sender_access hash:/usr/local/etc/postfix/access, permit_sasl_authenticated, permit_auth_destination, reject_unauth_destination
smtpd_sasl_auth_enable = yes
smtpd_sasl_local_domain = $mydestination
smtpd_sasl_security_options = noanonymous
smtpd_sender_restrictions = permit_sasl_authenticated