Postfix : Relay Access Denied

Root Cause

An error log appears in the postfix maillog during the email-sending process, this is because the network host/client-server of the email-sending application has not been added to the mynetworks configuration in postfix/


Open Postfix main configuration /etc/postfix/

$ nano /etc/postfix/

Add the host IP address on mynetworks conf

mynetworks =

Restart Postfix service

$ systemctl restart postfix