Subject: Returned mail: see transcript for details

From: Mail Delivery Subsystem <[email-masked]>
Date: Wed, 25 Oct 2006 16:33:12 +0200 (MET DST)

The original message was received at Wed, 25 Oct 2006 16:33:12 +0200 (MET DST)
from [email-masked] [131.176.33.3]

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

   ----- Transcript of session follows -----
... while talking to estecmta2.estec.esa.int.:
>>> RCPT To:<[email-masked]>
<<< 550 [email-masked]... No such user
550 5.1.1 <[email-masked]>... User unknown