We receive this error when sending email to a specific email address outside of our exchange 2007 environment. I was successfull in sending email to the same address from my hotmail account (I know this because they responded). We have no problems sending email to other companies outside of our environment. I even added the domain to the Accepted Domains list. Please Help. Delivery has failed to these recipients or distribution lists:<?xml:namespace prefix = o ns = "urn:schemas-microsoft-com:office:office" /><o:p></o:p> <o:p> </o:p> elm.ar@mcmaster.com The recipient's e-mail address was not found in the recipient's e-mail system. Microsoft Exchange will not try to redeliver this message for you. Please check the e-mail address and try resending this message, or provide the following diagnostic text to your system administrator.<o:p></o:p> Diagnostic information for administrators:<o:p></o:p> Generating server: ENONT21.EOPLASTICS.COM<o:p></o:p> elm.ar@mcmaster.com #550 5.1.1 RESOLVER.ADR.RecipNotFound; not found ## Original message headers:<o:p></o:p> Received: from ENONT21.EOPLASTICS.COM ([192.168.100.22]) by enont21.EOPLASTICS.COM ([192.168.100.22]) with mapi; Fri, 4 Nov 2011 15:15:07 -0500 Content-Type: application/ms-tnef; name="winmail.dat" Content-Transfer-Encoding: binary From: Chad Remick <chad.remick@eoplastics.com> To: "elm.ar@mcmaster.com" <elm.ar@mcmaster.com> Date: Fri, 4 Nov 2011 15:15:06 -0500 Subject: Test Email Thread-Topic: Test Email Thread-Index: AQHMmy5xn0ROEi7yK0yP6IYrAzlliA== Message-ID: <35C4E5619060834193717C4FEC936A799A036BF214@enont21.EOPLASTICS.COM> Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: <35C4E5619060834193717C4FEC936A799A036BF214@enont21.EOPLASTICS.COM> MIME-Version: 1.0 <o:p></o:p>

Adding the domain the Accepted Domains list is the last thing you want to do! That tells Exchange that your org is repsonsible for that SMTP domain.

Remove that domain as an accepted domain and try sending again. Turn on the logging on your Send connector and see what's going on, Do a nslookup on the Exch server and resolve the MX records to see if they are correct Sukh

Adding the domain the Accepted Domains list is the last thing you want to do! That tells Exchange that your org is repsonsible for that SMTP domain.

Remove that domain as an accepted domain and try sending again. Turn on the logging on your Send connector and see what's going on, Do a nslookup on the Exch server and resolve the MX records to see if they are correct Sukh

Hi, Sometimes Outlook cache might cause this problem. Please try to send email via OWA for test then feedback here. Thanks.Best Regards!

Hi, Sometimes Outlook cache might cause this problem. Please try to send email via OWA for test then feedback here. Thanks.Best Regards!

Hi, Any update?Best Regards!