Concern: -------- You would like to send mail with Open-Xchange Server over a provider relay, which needs SMTP authentication. Solution: --------- Currently it's not possible to activate this feature within the oxadmin framework, thus you have to configure this manually. You may follow these steps: - insert the following lines both into the postfix configuration file /etc/postfix/main.cf IMPORTANT: and its template (see main.cf) # SMTP-AUTH smtp_sasl_auth_enable = yes smtp_sasl_security_options = noanonymous smtp_sasl_password_maps = hash:/etc/postfix/sasl_passwd - create the file /etc/postfix/sasl_passwd with the following content: # password list for smtp-auth # # Relay host username:password # ------------------ ----------------- mail.example.tux johndoe:topsecret Use the credentials you have got by your provider. - create the hash table for this config file with # postmap /etc/postfix/sasl_passwd - finally restart postfix. Once you have configured the relayhost "mail.example.tux" within the SMTP configuration of the oxadmin framework, all mail is sent through the providers relayhost