strange mail

Tech-Archive recommends: Fix windows errors by optimizing your registry

I have an user that receives a day several mail like this:

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Microsoft Mail Internet Headers Version 2.0
Received: from mail pickup service by EXCHANGE.dc.dominio.intranet with
Microsoft SMTPSVC;
Fri, 15 Sep 2006 15:08:33 +0200
To: <usuario1@xxxxxxxxxxx>
From: <usuario1@xxxxxxxxxxx>
Message-ID: <49d8d08d72742a458fb424a826dfa2d4-b558a@OMA>
Subject: 42ace21ebc933f46842e2c8c76f3d9db-59f29
Date: vie sep 15 13:08:32 2006
Content-Type: text/plain; charset=iso-8859-1
X-OriginalArrivalTime: 15 Sep 2006 13:08:33.0185 (UTC)
FILETIME=[0BEE1910:01C6D8C8]
--

Does somebody know because?

Thank you


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