I'm running MailEnable on my server, and have been for many years. Recently we had an attack on our server, and I was able to close the hole.

Since then, our mail server doesn't seem to be sending mail out.

• If I send an email from myself to another account hosted on the server, the email arrives as expected.
• If I send an email from my gmail account to my business account, the email also arrives as expected
• The problem comes when I send from my business account to an external domain
  • I tried the following
    • Gmail.com
    • Hotmail.com
    • Shaw.ca
  • When I send to any of the above
    • The message leaves my client as expected,
    • The logs appear to accept and forward on the message
    • The SMTP outbound que is empty
    • The message never arrives
  • I have checked our domain with
    
    • mxtoolbox.com
    • senderbase.org
      • And neither of them are reporting any problems with our domain.
  • I have ensured that port 25 is open (along with the other standard ports)

Here is one of the log entries from the SMTP connector

11/05/13 12:10:00   SMTP-IN 494C0AF55CD0400FB90FD5E6525BC885.MAI    1312    127.0.0.1           220 mx1.example.com ESMTP MailEnable Service, Version: 6.81--6.81 ready at 11/05/13 12:10:00    0   0       
11/05/13 12:10:00   SMTP-IN 494C0AF55CD0400FB90FD5E6525BC885.MAI    1312    127.0.0.1   EHLO    EHLO ASSP.nospam    250-mx1.example.com [127.0.0.1], this server offers 6 extensions    159 18      
11/05/13 12:10:00   SMTP-IN 494C0AF55CD0400FB90FD5E6525BC885.MAI    1312    127.0.0.1   EHLO    EHLO ASSP.nospam    250-mx1.example.com [127.0.0.1], this server offers 6 extensions    159 18      
11/05/13 12:10:01   SMTP-IN 494C0AF55CD0400FB90FD5E6525BC885.MAI    1312    127.0.0.1   AUTH    AUTH LOGIN  334 VXNlcm5hbWU6    18  12      
11/05/13 12:10:01   SMTP-IN 494C0AF55CD0400FB90FD5E6525BC885.MAI    1312    127.0.0.1   AUTH    {blank} 334 UGFzc3dvcmQ6    18  26  [email protected]
11/05/13 12:10:01   SMTP-IN 494C0AF55CD0400FB90FD5E6525BC885.MAI    1312    127.0.0.1   AUTH    Y29sb25lbGZhY2U=    235 Authenticated   19  18  [email protected]   
11/05/13 12:10:01   SMTP-IN 494C0AF55CD0400FB90FD5E6525BC885.MAI    1312    127.0.0.1   MAIL    MAIL FROM:<[email protected]>   250 Requested mail action okay, completed   43  31  [email protected]   
11/05/13 12:10:01   SMTP-IN 494C0AF55CD0400FB90FD5E6525BC885.MAI    1312    127.0.0.1   RCPT    RCPT TO:<[email protected]>   250 Requested mail action okay, completed   43  35  [email protected]   
11/05/13 12:10:01   SMTP-IN 494C0AF55CD0400FB90FD5E6525BC885.MAI    1312    127.0.0.1   DATA    DATA    354 Start mail input; end with <CRLF>.<CRLF>    46  6   [email protected]   

Here are the headers of the sent message

X-Assp-Version: 1.7.5.7(1.0.07) on ASSP.nospam
X-Assp-ID: ASSP.nospam 78601-04523
X-Assp-Intended-For: [email protected]
X-Assp-Envelope-From: [email protected]
Received: from [10.10.1.101] ([68.147.245.149] helo=[10.10.1.101]) with
    IPv4:587 by ASSP.nospam; 5 Nov 2013 12:10:00 -0700
From: Chase Florell <[email protected]>
Content-Type: text/plain
Content-Transfer-Encoding: 7bit
Subject: Test Message
Message-Id: <[email protected]>
Date: Tue, 5 Nov 2013 12:10:18 -0700
To: Chase Florell <[email protected]>
Mime-Version: 1.0 (Mac OS X Mail 7.0 \(1816\))
X-Mailer: Apple Mail (2.1816)

.

Where else can I check to see if there is something broken? What could cause a problem like this whereby the message appears to send, but never arrives, and never returns a bounce?