I think SMTP-AUTH is very important! Here is a short HowTo for Postfix with sasl authentication against shadow. First install the necessary packages: apt-get install postfix-tls libsasl2-modules sasl2-bin Open the /etc/default/saslauthd for the configuration. # This needs to be uncommented before saslauthd will be run automatically START=yes # You must specify the authentication mechanisms you En savoir plus surPostfix with SASL-Authentication in Debian – Jonas Genannt[…]