Question : Getting bounced mail I did not send

Here is the header of an email I did not send, that bounced back to me.  I changed the domain name for privacy reasons.
Is there a way to tell from this if someone is just using my return address, or actually using my server to send email?
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Microsoft Mail Internet Headers Version 2.0
Received: from aci1 ([192.168.102.25]) by aci1.acintz.officentz.aci with Microsoft SMTPSVC(6.0.3790.1830);
       Tue, 4 Sep 2007 04:28:01 -0400
Received: from pop.1and1.com
          by anything.com with POP3; Tue, 4 Sep 2007 04:28:00 -0400
Return-Path: <>
Delivery-Date: Tue, 04 Sep 2007 04:23:46 -0400
Received-SPF: none (mxus3: 193.252.22.21 is neither permitted nor denied by domain of smtp25.orange.fr) client-ip=193.252.22.21; envelope-from=postmaster@smtp25.orange.fr; helo=smtp25.orange.fr;
Received: from [193.252.22.21] (helo=smtp25.orange.fr)
      by mx.perfora.net (node=mxus3) with ESMTP (Nemesis),
      id 0MKofY-1ISThJ21ip-0001vU for [email protected]; Tue, 04 Sep 2007 04:23:45 -0400
Received: by mwinf2530.orange.fr (SMTP Server)
      id 5D21C1C05D34; Tue,  4 Sep 2007 03:13:14 +0200 (CEST)
Date: Tue,  4 Sep 2007 03:13:14 +0200 (CEST)
X-ME-UUID: 20070902123737998.F3C8D1C00091@mwinf2558.orange.fr
From: [email protected] (Mail Delivery System)
Subject: Undelivered Mail Returned to Sender
To: [email protected]
MIME-Version: 1.0
Content-Type: multipart/report; report-type=delivery-status;
      boundary="A26F21C57295.1188868394/orange.fr"
Message-Id: <20070904011314.5D21C1C05D34@mwinf2530.orange.fr>
X-SpamScore:   2
      tests= DATE_IN_PAST_06_12 RDNS_NONE
Envelope-To: [email protected]
X-OriginalArrivalTime: 04 Sep 2007 08:28:01.0859 (UTC) FILETIME=[81E91130:01C7EECD]

--A26F21C57295.1188868394/orange.fr
Content-Description: Notification
Content-Type: text/plain

--A26F21C57295.1188868394/orange.fr
Content-Description: Delivery report
Content-Type: message/delivery-status

--A26F21C57295.1188868394/orange.fr
Content-Description: Undelivered Message
Content-Type: message/rfc822

Received: from smtp25.orange.fr (mwinf2558 [10.232.9.166])
      by mwinf2530.orange.fr (SMTP Server) with ESMTP id A26F21C57295
      for ; Sun,  2 Sep 2007 14:37:42 +0200 (CEST)
Received: from me-wanadoo.net (localhost [127.0.0.1])
      by mwinf2558.orange.fr (SMTP Server) with ESMTP id 862EA1C0008E
      for ; Sun,  2 Sep 2007 14:37:42 +0200 (CEST)
Received: from [192.168.11.2] (LAubervilliers-151-11-53-125.w193-251.abo.wanadoo.fr [193.251.89.125])
      by mwinf2558.orange.fr (SMTP Server) with SMTP id F3C8D1C00091;
      Sun,  2 Sep 2007 14:37:37 +0200 (CEST)
X-ME-UUID: 20070902123737998.F3C8D1C00091@mwinf2558.orange.fr
Message-ID: <001c01c7edc2$a09664ae$6a9cd28d@thmjszoj>
From: "=?windows-1251?B?S2F0cmlu?="
To: , ,
      , ,
      , ,
      , ,
      , ,
      , , ,
      ,
Subject: =?windows-1251?B?TG9va2luZyBmb3IgYSB3aWZlPw==?=
Date: Sun, 2 Sep 2007 14:45:16 +0200
MIME-Version: 1.0
Content-Type: text/plain;
      charset="windows-1251"
Content-Transfer-Encoding: 7bit
X-Priority: 3
X-MSMail-Priority: Normal
X-Mailer: Microsoft Outlook Express 6.00.2600.0000
X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2600.0000


--A26F21C57295.1188868394/orange.fr--

Answer : Getting bounced mail I did not send

Looks like a spoofed email to me.
If you don't see anything in the headers of the original message that points at your server, then it is most likely a spoof. Nothing much you can do about those.

Simon.