Re: SMTP cannot open Port 25

From: Kristofer Gafvert (kgafvert_at_NEWSilopia.com)
Date: 04/20/04 

Date: Tue, 20 Apr 2004 09:15:19 +0200

Hello,

One way to do this is to have a local SMTP server installed on the
webserver, but port 25 is closed. There will be nothing communicating with
that machine on port 25, it will only send the emails to another machine, so
there is no reason to have port 25 open.

You then configure a smart host, which will send the emails out on Internet.
Make sure that localhost can relay on the webserver's SMTP server, other
than that, do not add anything (so if someone accidently opens the port, it
will still not be possible to abuse the SMTP server, because nobody can
relay using it, except if you send from localhost).

Another way to do this is to edit your scripts so that you can send emails
directly with the other SMTP server (you might need to authenticate or
something, i do not know that). 

-- 
Regards,
Kristofer Gafvert - IIS MVP
Reply to newsgroup only. Remove NEWS if you must reply by email, but please
do not.
http://www.ilopia.com/
"Beau Bennett" <beau@REMOVETHIStheclip.com> wrote in message
news:15b101c426a3$346eae10$a501280a@phx.gbl...
> I have a single site on a Windows 2003 Web Server Edition
> that uses several scripts to send email out. I am not
> using this server for SMTP or DNS, as those are totally
> separate servers. We've tweaked the the server settings
> til' we're blue in the face. We've made certain the SMTP
> snap-in is in the IIS 6 console. We've installed and
> uninstalled the SMTP service. All we want is the server to
> send the mail out to our (separate) SMTP server.
>
> We found a MS knowledgebase article (323350) titled "HOW
> TO: Test SMTP Services Manually in Windows Server 2003"
> http://support.microsoft.com/default.aspx?kbid=323350
>
> We ran the Telnet test and it appears that Port 25 is
> CLOSED to SMTP traffic. A copy of the result is below:
> ++++++++++++++++++++++++++++
> Welcome to Microsoft Telnet Client
> Escape Character is 'CTRL+]'
> Microsoft Telnet> set LocalEcho
> Local echo on
> Microsoft Telnet> open <theclip> 25
> Connecting To <theclip>...Could not open connection to the
> host, on port 25: Connect failed
> Microsoft Telnet> open <theclip.com> 25
> Connecting To <theclip.com>...Could not open connection to
> the host, on port 25:
>  Connect failed
> ++++++++++++++++++++++++++++
> Also, what is a typical 'LocalHost' setting for a web
> server like this?
> We would be eternally grateful (not to mention very
> Generou$$) if someone could help us solve this problem.
>
> Beau Bennett - (One small step from crazy)
> 858-549-3121
> San Diego, CA

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