Mail Delivery host error

[ianedwards]

HI
I'm not sure what my problem is so I thought I'd ask in the hope of some help.

I rent/own a windows 2003 server running iis v6 which I use to host 20 or so web sites I look after.

One domain has problems sending mail to some addresses allways the same three domains. the exact error message is below .

I contacted the company (fasthosts) who setup the server and they suggested I do the following:-

Your problem can be resolved by a change in the registry settings of your Server.

Anyone telnetting to your server over port 25 (the mail port) is presented with 'matrix' as the name instead of the domain paktec.co.uk, hence mail from the server can be blocked as can viewed by checing systems as potential spam. This can be solved via the registry hack below.

“HKEY_LOCAL_MACHINE\SOFTWARE\Matrix\Mail Service”

HELOIdent - String Value (REG_SZ)

They declined to give me explicit instructions. So I went to the registry added a new key called HELOIdent and left the string box blank

Can anyone throw any light on this?

the error message received is below

thanks

Ian

Send failed due to: Unable to resolve host
Original message follows:

Received: From 82-71-62-38.dsl.in-addr.zen.co.uk [xx.71.62.38] by
[yy.171.206.211]
(Matrix SMTP Mail Server v(1.4))
ID=72819BD3-43D4-4060-AEC7-8A41E2F46C4E ; Fri, 22 Sep 2006 14:51:50
+0100
Subject: nick@test.com
MIME-Version: 1.0
Content-Type: text/plain;
charset="iso-8859-1"
Content-Transfer-Encoding: quoted-printable
Date: Fri, 22 Sep 2006 14:58:37 +0100
Disposition-Notification-To: "Anna Smith" <anna@test.co.uk>
X-MimeOLE: Produced By Microsoft Exchange V6.0.4417.0
Message-ID:
<664328BE526BA44DBB4583F75B8092BB03E387@ptserver.smith.co.uk>
X-MS-Has-Attach:
content-class: urn:content-classes:message
X-MS-TNEF-Correlator:
Thread-Topic: nick@test1.com
Thread-Index: AcbeTj8IZBrMXYzGSvO7Q/lL4ByW9A==
From: "Anna Smith" <anna@test.co.uk>
To: <nick@test1.com>
X-RCPT-TO: <nick@test1.com>

 

[avilov]

That is because your MX records points to mail.your-domain.co.uk but reverse resolution of the yy.171.206.211 is server206-211.other-domain.net

 

[ianedwards]

Hi

thanks for that I have contacted the DNS holder who has said

"It is true that some providers can be funny about the reverse DNS lookup.

If you believe the reverse DNS of your server IP address is causing problems, let us now what you want us to change the reverse DNS to and we can process this for you."

Do I need to ask them to ensure that the reverse DNS ip points to the MX ip address?

thanks

Ian