Re: "Phone home" mail script for MS-Windows

Frank Slootweg <this@xxxxxxxxxxxxxxxxx> writes:

Neil Woods <cnw+usenet-0603@xxxxxxxxx> wrote:
Tristan Miller <psychonaut@xxxxxxxxxxxxxxxxx> writes:

How do you propose to figure out which mail server to connect to, given
that you know nothing about the network the machine is connected to?

I can have it connect to my own mail server.

This would not work if the gateway ISP forwards port 25 connections to
their own SMTP server, which many do. Does your mail server listen on a
non-standard port or use port 587 (submission - RFC2476)?

It wouldn't be so bad if they would "forward" (whatever you mean by
that) them, but many/most consumer-grade ISPs *block* outgoing port 25
connections to any mailserver other than their own, i.e. when you try to
connect, you get an error message.

You are quite correct. E.g.

% telnet mail.messagingengine.com 25
Trying 66.111.4.160...
Connected to mail.messagingengine.com.
Escape character is '^]'.
554 Please check your SMTP server is set to smtp.wanadoo.co.uk.
Further help is available at
http://www.wanadoo.co.uk/help/email/freeserveemailsettings/outlooksettings.htm
Connection closed by foreign host.

However, they (i.e. Wanadoo, previously Freeserve here in the UK) didn't
used to do this. Previously, the connection would succeed, and it would
*appear* that you were connecting to the requested server, but the
connection would be *really* to your own ISP's mail server.

Perhaps "proxy" would have been a better word to use, rather than
"forward" (it's been a while since I tested this). However, this is all
moot now, as they do indeed *block* these connections now.

--
Neil.
Moderation in all things.
-- Publius Terentius Afer [Terence]
.

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