* The [https://tools.ietf.org/html/rfc6409 submissions] port (465) is preferred for email relay. Unauthenticated and unencrypted connections are not allowed to relay. | * The [https://tools.ietf.org/html/rfc6409 submissions] port (465) is preferred for email relay. Unauthenticated and unencrypted connections are not allowed to relay. |