Subject: Returned mail: see transcript for details

From: Mail Delivery Subsystem <[email-masked]>
Date: Wed, 24 Sep 2008 13:00:51 -0600 (MDT)

The original message was received at Wed, 24 Sep 2008 12:59:49 -0600 (MDT)
from [189.73.238.179]

   ----- The following addresses had permanent fatal errors -----
<[email-masked]>
    (reason: 550 5.1.1 unknown or illegal user: [email-masked])

   ----- Transcript of session follows -----
... while talking to emss09g01.ems.lmco.com.:
>>> DATA
<<< 550 5.1.1 unknown or illegal user: [email-masked]
550 5.1.1 <[email-masked]>... User unknown
<<< 554 5.5.0 No recipients have been specified.