Subject: Undelivered Mail Returned to Sender
From: [email-masked] (Mail Delivery System)
To: [email-masked]
Date: Thu, 27 Oct 2011 12:29:35 +0100 (BST)

This is the mail system at host admin1.example.co.uk.

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

<[email-masked]>: message size 18876259 exceeds size
    limit 10485760 of server cluster.thor.test.co[82.197.78.148]