another email problem

I have an email address that I am trying to connect to. It is a remote address not set up on our server. I am able to reply to his emails fine when he sends me one. But if I try to generate a new email to the same address it always fails. The only difference I see in the log other than that one fails, is that when I reply to his email it shows

"relay=mx.central.cox.net"

where as when I create a new email that fails it says

"relay=none"

any ideas on where I need to look for a solution to this? Let me know if you need other information.

 

What's the recipient domain?

Can you post the header of an email he sends to you?

 

The recipient domain is cox.net. Here are the headers from the email that he sent to me that I was able to reply to.

Return-Path: <[email protected]>
X-Original-To: [email protected]
Delivered-To: [email protected]
Received: from fed1rmmtao04.cox.net (unknown [68.230.241.35])
by server1.notui.com (Postfix) with ESMTP id 911382FA30
for <[email protected]>; Tue, 7 Mar 2006 13:22:01 -0800 (PST)
Received: from jimc88lia0clsw ([68.110.93.99]) by fed1rmmtao04.cox.net
(InterMail vM.6.01.05.02 201-2131-123-102-20050715) with SMTP
id <20060307211807.PLXN17690.fed1rmmtao04.cox.net@jimc88lia0clsw>
for <[email protected]>; Tue, 7 Mar 2006 16:18:07 -0500
Message-ID: <000d01c64235$b554a0c0$0200a8c0@jimc88lia0clsw>
From: "user Name" <[email protected]>
To: <[email protected]>
Subject: Fw: test
Date: Tue, 7 Mar 2006 14:23:06 -0800
MIME-Version: 1.0
Content-Type: multipart/alternative;
boundary="----=_NextPart_000_000A_01C641F2.A7082DE0"
X-Priority: 3

 

What's the output of

Code:

dig mx cox.net

on your system? What's in /etc/resolv.conf?