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Hi,<br />
<br />
In the last day or so, we start getting our emails rejected by a certain domain with the following message:<br />
<br />
I'm sorry to inform you that the message below could not be delivered.<br />
When delivery was attempted, the following error was returned.<br />
&nbsp;Name or service not known.<br />
<br />
The problem is that I don't know on which side is the &quot;name or service not known&quot;. <br />
<br />
<br />
We were able to send a couple of days ago. <br />
<br />
<br />
Thank you so much for your help!
</div>
</div>


Hi,

In the last day or so, we start getting our emails rejected by a certain domain with the following message:

I'm sorry to inform you that the message below could not be delivered.
When delivery was attempted, the following error was returned.
 Name or service not known.

The problem is that I don't know on which side is the "name or service not known". 


We were able to send a couple of days ago. 


Thank you so much for your help!

Email rejected: Name or service not known

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

An email client, email reader or more formally mail user agent (MUA) is a computer program in the category of groupware environments used to access and manage a user's email. A web application that provides message management, composition, and reception functions may internally act as an email client; as a whole, it is commonly referred to as webmail. Likewise, email client may be referred to a piece of computer hardware or software whose primary or most visible role is to work as an email client. Email clients can also have other systems, like calendars, notes and contact managers.

Email Clients

Various techniques are used to prevent email spam (unsolicited bulk email). No technique is a complete solution to the spam problem, and each has trade-offs between incorrectly rejecting legitimate email (false positives) vs. not rejecting all spam (false negatives) - and the associated costs in time and effort. Anti-spam techniques can be broken into four broad categories: those that require actions by individuals, those that can be automated by email administrators, those that can be automated by email senders and those employed by researchers and law enforcement officials.