Subject: Returned mail: see transcript for details

From: Mail Delivery Subsystem <[email-masked]>
Date: Wed, 15 Oct 2008 08:03:37 +0200

The original message was received at Wed, 15 Oct 2008 08:03:26 +0200
from localhost [127.0.0.1]

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

   ----- Transcript of session follows -----
... while talking to [62.160.164.187]:
>>> DATA
<<< 550 5.1.1 User unknown
550 5.1.1 <[email-masked]>... User unknown
<<< 503 5.5.2 Need Rcpt command.