<div>
The remote site thinks you are on a dynamic IP address. Are you? If so then you will need to use an SMTP connector to route email for that domain and others via your ISPs SMTP Server. <br />
<a href="http://www.amset.info/exchange/smtp-connector.asp" rel="ugc">http://www.amset.info/exchange/smtp-connector.asp</a><br />
<br />
It could also be that the remote domain isn't setup correctly and is pointing their MX records at the wrong host. <br />
<br />
Simon. 
</div>


The remote site thinks you are on a dynamic IP address. Are you? If so then you will need to use an SMTP connector to route email for that domain and others via your ISPs SMTP Server.
http://www.amset.info/exchange/smtp-connector.asp [http://www.amset.info/exchange/smtp-connector.asp]

It could also be that the remote domain isn't setup correctly and is pointing their MX records at the wrong host.

Simon.

<div>
No we are on a fixed IP. The recipient says they have no problem getting mail from anyone else. We use reverse DNS lookup and our public ip address is in the MX record for our domain
</div>


No we are on a fixed IP. The recipient says they have no problem getting mail from anyone else. We use reverse DNS lookup and our public ip address is in the MX record for our domain

<div>
<div class="content wysiwyg-content">
I am getting this error when sending to a specific email address . I use Exchange 2003.I only have this problem with this address and have tried sending it from a hotmail account which works fine. Any ideas ?<br />
<br />
Your message did not reach some or all of the intended recipients.<br />
<br />
&nbsp; &nbsp; &nbsp; Subject: &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Help<br />
&nbsp; &nbsp; &nbsp; Sent: &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;16/04/2009 14:22<br />
<br />
The following recipient(s) cannot be reached:<br />
&nbsp; &nbsp; &nbsp; &nbsp; <br />
&nbsp; &nbsp; There was a SMTP communication problem with the recipient's email server. &nbsp;Please contact your system administrator.<br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &lt;&quot;mydomain.co.uk&quot; #5.5.0 smtp;550 Submission from dynamic &quot;my IP Address &quot;requires authentication&gt;<br />
<br />

</div>
</div>


I am getting this error when sending to a specific email address . I use Exchange 2003.I only have this problem with this address and have tried sending it from a hotmail account which works fine. Any ideas ?

Your message did not reach some or all of the intended recipients.

      Subject:	Help
      Sent:	16/04/2009 14:22

The following recipient(s) cannot be reached:
        
    There was a SMTP communication problem with the recipient's email server.  Please contact your system administrator.
            <"mydomain.co.uk" #5.5.0 smtp;550 Submission from dynamic "my IP Address "requires authentication>



I have an SMTP communication problem .

Microsoft server applications are those applications developed specifically, but not necessarily exclusively, on the Windows Server platform. In addition to well-known products like SQL Server, Exchange, Internet Information Services (IIS), Microsoft Dynamics, Forefront, Lync and Sharepoint, they include applications like Skype, BizTalk, Hyper-V, Groove and Commerce Server. Server applications are managed with the Microsoft System Center.

Microsoft Server Apps

Exchange is the server side of a collaborative application product that is part of the Microsoft Server infrastructure. Exchange's major features include email, calendaring, contacts and tasks, support for mobile and web-based access to information, and support for data storage.