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Perhaps this might help: <a href="http://www.bloggylife.com/2009/05/27/email-error-invalid-ehlohelo-domain/" rel="ugc">http://www.bloggylife.com/2009/05/27/email-error-invalid-ehlohelo-domain/</a>
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Perhaps this might help: http://www.bloggylife.com/2009/05/27/email-error-invalid-ehlohelo-domain/ [http://www.bloggylife.com/2009/05/27/email-error-invalid-ehlohelo-domain/]

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The only thing that follows SMTP HELO or EHLO is the connecting system's fully-qualified name, e.g.<br />
<br />
HELO mail.yahoo.com<br />
EHLO smtp.somewhere.org<br />
<br />
&quot;Invalid EHLO/HELO domain&quot; is a peculiar way to phrase this error message. &nbsp;Two possibilities come to mind:<br />
<br />
a) It directly refers to the HELO/EHLO fully-qualified name. &nbsp;The only thing that can be wrong is that the fully-qualified name is somehow unacceptable to the receiving system's SMTP server.<br />
<br />
b) It indirectly refers to the fully-qualified name in the HELO/EHLO. &nbsp;What it really means is &quot;Your name is badly formed,&quot; &quot;I can't do an RDNS on your name,&quot; or &quot;I've got a blacklist and you're on it.&quot;<br />
<br />
There are some other possibilities as well. &nbsp;See the description of SMTP status 550 at <a href="http://www.answersthatwork.com/Download_Area/ATW_Library/Networking/Network__3-SMTP_Server_Status_Codes_and_SMTP_Error_Codes.pdf" rel="ugc">this PDF page</a><br />
<br />

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The only thing that follows SMTP HELO or EHLO is the connecting system's fully-qualified name, e.g.

HELO mail.yahoo.com
EHLO smtp.somewhere.org

"Invalid EHLO/HELO domain" is a peculiar way to phrase this error message.  Two possibilities come to mind:

a) It directly refers to the HELO/EHLO fully-qualified name.  The only thing that can be wrong is that the fully-qualified name is somehow unacceptable to the receiving system's SMTP server.

b) It indirectly refers to the fully-qualified name in the HELO/EHLO.  What it really means is "Your name is badly formed," "I can't do an RDNS on your name," or "I've got a blacklist and you're on it."

There are some other possibilities as well.  See the description of SMTP status 550 at this PDF page [http://www.answersthatwork.com/Download_Area/ATW_Library/Networking/Network__3-SMTP_Server_Status_Codes_and_SMTP_Error_Codes.pdf]



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I'm trying to send an e-mail to a mail server from my Exchange Server 2007 but I got an error: &nbsp;550 5.5.0 Invalid EHLO/HELO domain<br />
<br />
What should I do?<br />
<br />
Thanks.
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I'm trying to send an e-mail to a mail server from my Exchange Server 2007 but I got an error:  550 5.5.0 Invalid EHLO/HELO domain

What should I do?

Thanks.

550 5.5.0 Invalid EHLO/HELO domain

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

Within Internet message handling services (MHS), a message transfer agent or mail transfer agent (MTA) or mail relay is software that transfers electronic mail messages from one computer to another using a client–server application architecture. A MTA implements both the client (sending) and server (receiving) portions of the Simple Mail Transfer Protocol (SMTP). The terms mail server, mail exchanger, and MX host may also refer to a computer performing the MTA function. The Domain Name System (DNS) associates a mail server to a domain with mail exchanger (MX) resource records containing the domain name of a host providing MTA services.