SMTP error the remote server did not respond to a connection attem   

We have a SMTP Service setup in IIS 6.0 for sending mail from a website. This 
service will randomly have an error that says "Message delivery to the host 
<ip> failed while delivering to the remote domain <domain name> for the 
following reason: The remote server did not respond to a connection attempt" 
This error happens randomly and when this happens the mail that was trying to 
be sent is not received. The mail is in the badmail folder on the server. 
This server is in the DMZ and is in between a front and back ISA 2006 
firewall. Does anyone have any ideas as to what this error means or how to 
correct this problem? This has been happening for about 3 months now and was 
working fine before.

date: Thu, 5 Jun 2008 14:23:00 -0700   author:   emhrdng

Re: SMTP error the remote server did not respond to a connection attem   

> We  have  a  SMTP  Service  setup in IIS 6.0 for sending mail from a
> website. This service will randomly have an error that says "Message
> delivery  to  the  host  <ip>  failed while delivering to the remote
> domain <domain name> for the following reason: The remote server did
> not respond to a connection attempt"

It's  almost  certainly  not  "random" -- nothing in SMTP really is. A
major  difficulty in supporting mailservers is that must know not only
the RFC (standard) failure points for DNS and SMTP, but you must learn
to   intuit   the   use  of  non-standard  anti-spam/anti-abuse  "best
practices"  that  can  be  equally  disruptive  to  mail delivery. The
permutations are staggering -- though not unlimited.

First  off,  consult  your  logs.  The Event Viewer summary events are
hardly sufficient for diagnosing delivery problems.

Next,  download MS' SMTPDIAG tool and run it, from the mailserver, for
the exact sender and recipient in question.

Third, does your mailserver pass the PTR-EHLO-A roundtrip check? Check
the archives of this list for my many posts on this.

--Sandy



------------------------------------
Sanford Whiteman, Chief Technologist
Broadleaf Systems, a division of
Cypress Integrated Systems, Inc.
------------------------------------

date: Thu, 05 Jun 2008 18:52:54 -0400   author:   Sanford Whiteman