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<br />
That error indicates there is some problem during the mail flow which is preventing any relaying of mail taking place. There is either a mis-configuration on the recipient's server, or an error on one of the hops between you and them.<br />
<br />
How do you send email out? Via direct delivery (DNS) or smart host? If the former, I would suggest it is their error. However, if the latter, you may want to check your smart host configuration has not changed, or check with the ISP if they have made any changes.<br />
<br />
-Matt
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That error indicates there is some problem during the mail flow which is preventing any relaying of mail taking place. There is either a mis-configuration on the recipient's server, or an error on one of the hops between you and them.

How do you send email out? Via direct delivery (DNS) or smart host? If the former, I would suggest it is their error. However, if the latter, you may want to check your smart host configuration has not changed, or check with the ISP if they have made any changes.

-Matt

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We do not use a smart host, Exchange 2003, direct delivery.<br />
<br />
It's only happening with one domain, very strange. &nbsp;Makes me think they made a change since we have made none.
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We do not use a smart host, Exchange 2003, direct delivery.

It's only happening with one domain, very strange.  Makes me think they made a change since we have made none.

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Hello, we are using SBS 2003. Nothing has changed on our end.<br />
<br />
When we try to email on domain in particular, which we used to be able to email without any problems at all, we are now getting Relaying denied. Proper authentication required.<br />
<br />
I have not changed anything on our server, could it be on their end? &nbsp;Any suggestions?<br />
<br />
Thank you
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Hello, we are using SBS 2003. Nothing has changed on our end.

When we try to email on domain in particular, which we used to be able to email without any problems at all, we are now getting Relaying denied. Proper authentication required.

I have not changed anything on our server, could it be on their end?  Any suggestions?

Thank you

Relaying denied. Proper authentication required

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.

Exchange

Small Business Server (SBS) is a line of server operating systems targeted at small businesses by bundling the operating system with a number of other Microsoft products that would normally need to be purchased or licensed separately. The most notable inclusions are Exchange, SQL Server, SharePoint and ISA/TMG (Microsoft's firewall and proxy server).