Subject: Returned mail: see transcript for details

From: Mail Delivery Subsystem <[email-masked]>
Date: Thu, 21 Aug 2008 22:44:21 +0200 (CEST)

The original message was received at Thu, 21 Aug 2008 22:44:21 +0200 (CEST)
from localhost [127.0.0.1]

   ----- The following addresses had permanent fatal errors -----
<[email-masked]>
    (reason: 550 [email-masked]... No such user)

   ----- Transcript of session follows -----
... while talking to kluber-notes2.us.kluber.com.:
>>> DATA
<<< 550 [email-masked]... No such user
550 5.1.1 <[email-masked]>... User unknown
<<< 503 Issue RCPT TO: command before DATA command