Subject: [Gary] Returned mail: see transcript for details

From: Mail Delivery Subsystem <[email-masked]>
Date: Tue, 29 Apr 2008 05:53:20 +0200 (CEST)

The original message was received at Tue, 29 Apr 2008 05:52:24 +0200 (CEST)
from localhost [127.0.0.1]

   ----- The following addresses had permanent fatal errors -----
<[email-masked]>
    (reason: 550 <[email-masked]>: Recipient address rejected: User unknown in virtual mailbox table)

   ----- Transcript of session follows -----
... while talking to spamgate.igd.fraunhofer.de.:
>>> DATA
<<< 550 <[email-masked]>: Recipient address rejected: User unknown in virtual mailbox table
550 5.1.1 <[email-masked]>... User unknown
<<< 554 Error: no valid recipients