On 10/10/2018 12:52 AM, J. P. Gilliver (John) wrote [in part]:
In message ,I also wrote in part:
My Internet connection is through Spectrum, which also provides cable TV
service in my community. When it was Time Warner Cable before the
merger, they insisted I use their domain in my E-mail address. For that

For _outgoing_ emails. And incoming ones if you wanted those emails to
come via them.

That is because of how Time Warner operated. It is not a result of any
limitation in my Thunderbird E-mail client or in the POP3/SMTP
definitions. I have not checked to see if Spectrum still enforces this
restriction.


reason, I subscribed to E-mail and Web hosting from Sunset.net at
http://sunset.net/index.html, which does not impose such a limitation.
(I do still have such an E-mail address with a roadrunner.com domain,
which I only use as a backup for sending messages on the rare occasion
when Sunset.net goes down.)

For _incoming_ emails, what is the format of your address - does it end
in @yourdomain.*? If so, it must come via Sunset. Not your ISP
(Spectrum). If someone emails @yourdomian, "the internet" does not know
to send it to Spectrum. So you are using the _incoming_ email server
(POP or IMAP) at Sunset. For outgoing (SMTP), you could be using a
server at either, assuming Spectrum have one and allow you to use a
non-Spectrum From: address.

Both outgoing and incoming E-mail messages, I use the same E-mail
address. The address uses my rossde.com domain.

Actually, I have four E-mail addresses, all using the rossde.com domain.
Three of them get routed to my computer because I setup Thunderbird to
access those addresses. The fourth one gets routed to my wife's
computer, again because I setup Thunderbird on her computer to access
that address. I can tell from the header sections in the message
sources that all these messages indeed come through Sunset.net's POP3
server. Furthermore, I also see a connection to Sunset.net's SMTP
server when I send E-mail.

--
David E. Ross
http://www.rossde.com

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