[Trhm-Go] Undelivered Mail Returned to Sender

[Mail Delivery System]

This is the mail system at host filterbck03.colt-engine.it.

I'm sorry to have to inform you that your message could not
be delivered to one or more recipients. It's attached below.

For further assistance, please send mail to postmaster.

If you do so, please include this problem report. You can
delete your own text from the attached returned message.

                   The mail system

<dee567466dc982c7672 at sesia.it>: host 10.0.11.116[10.0.11.116] said: 550
    "Unknown User" (in reply to RCPT TO command)
-------------- next part --------------
An embedded message was scrubbed...
From: unknown sender
Subject: no subject
Date: no date
Size: 1340
URL: <http://list.pvv.org/pipermail/trhm-go/attachments/20140414/8e45a320/attachment.mht>