diff --git a/2.Common_services/1.Postfix/main.cf b/2.Common_services/1.Postfix/main.cf
index f056d786f2ed473c77fe1600a53eb78d4e3c511e..e67a0d3befe4c11c7b6404a0030d9e9097a6488f 100644
--- a/2.Common_services/1.Postfix/main.cf
+++ b/2.Common_services/1.Postfix/main.cf
@@ -10,9 +10,10 @@ append_dot_mydomain = no
 #delay_warning_time = 4h
 
 # 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_use_tls=yes
+smtpd_tls_cert_file = /etc/ssl/certs/ssl-cert-snakeoil.pem
+smtpd_tls_key_file = /etc/ssl/private/ssl-cert-snakeoil.key
+smtpd_use_tls = yes
+smtpd_relay_restrictions = permit_mynetworks permit_sasl_authenticated reject_unauth_destination
 smtpd_tls_session_cache_database = btree:${queue_directory}/smtpd_scache
 smtp_tls_session_cache_database = btree:${queue_directory}/smtp_scache