So I have played around with my attempts to get smtpmail working with
starttls -- including a wonderful 2 hours with a debugger trying to
work out the SMTP protocol.
It turns out that, in fact, my attempts to configure smtpmail were,
actually, correct. The problem is that smptmail.el doesn't work on
windows with starttls and this is, in fact, a known issue.
I even got as far as working out the reason -- which is also a known
issue -- which comes down to starttls's use of interrupts to gnutls
which windows can't do. Anyway, that is documented here.
As far as I can tell, this information is not actually in the smtpmail
documentation; I thought I'd post the story here, in the hope that it
will save anyone else from wasting their time trying to get this to
work. The error of my ways is that I searched over the *gnus* mailing
lists/news groups, where as this information appeared in *emacs*
What a pity -- getting the IMAP reader of gnus working with ssl
consisted of putting a single keyword into the mail sources. Enabling
sending mail in the same way appears to be nothing like as simple.
Or even possible.
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