Question : Mail delivery has failed

Dear expert

We are using co-existing mail solution right now and getting some problem when sending mail to a correct address.

Note: mail1.company.com is exchange 2003, mail2.company.com is exchange 2010.

We got a mail return whenever we are trying to send this mail:

Delivery has failed to these recipients or groups:

[email protected]
A communication failure occurred during the delivery of this message. Please try resending the message later. If the problem continues, contact your helpdesk.









Diagnostic information for administrators:

Generating server: mail1.company.com (This is exchange 2003)

[email protected]
#< #5.5.0 smtp;550 RCPT TO:<[email protected]> User unknown> #SMTP#

Original message headers:

Received: from mail2.company.com ([192.168.1.12]) by
 mail1.company.com with Microsoft SMTPSVC(6.0.3790.3959);       Thu, 20 May
 2010 12:51:59 +0200
Received: from mail2.company.com ([::1]) by mail2.company.com
 ([::1]) with mapi; Thu, 20 May 2010 12:51:59 +0200
From: =?iso-8859-1?Q?user1= <[email protected]>
Subject: =?iso-8859-1?Q?FW:=
Thread-Topic: =?iso-8859-1?Q?St==
Thread-Index: Acrt462FPl+kTgicSyGrqEFfyS+IPgKI+3FA
Date: Thu, 20 May 2010 10:51:57 +0000
Message-ID: <B4561EA180D19D4DA9707CF6A5B6BD9802C3ED@mail2.company.com>
Accept-Language: en-US
Content-Language: en-US
X-MS-Has-Attach:
X-MS-TNEF-Correlator:
Content-Type: multipart/alternative;
      boundary="_000_B4561EA180D19D4DA9707CF6A5B6BD9802C3ED"
MIME-Version: 1.0
BCC:
Return-Path: [email protected]
X-OriginalArrivalTime: 20 May 2010 10:51:59.0546 (UTC) FILETIME=[78EA41A0:01CAF80A]

Any expert know what could be the problem? the mail address is correct. the mail address is edited because company policy.

Answer : Mail delivery has failed

Folow the snapshot in Exchange System Manager

Untitled.png (52 KB) (File Type Details) 

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