I ask because as Bruce Schneier pointed out, his email security's only as good as that of the people he messages. With so many people using gmail, outlook, yahoo, etc., striving for total privacy is expensive.
Thus, I politely wonder whether you've set unrealistic expectations.
For services we have running that send email but don't know how to encrypt (like Redmine and Jenkins), I wrote a little smtp proxy that all it does is look at the from and to addresses, select appropriate keys, construct a new encrypted email and forward it to the real smtp server. It's written in Python and is super-simple but has worked for years now.
A few companies (and their associated governments) have vast central databases containing most of the world's mail. At one point that would've been considered dystopian, but today many people just take it for granted.
I've previously worked in financial technology, and even financial advisors dealing with sensitive client info would always just use plain email.
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If you're comfortable telling me: what country and industry are you in?
Is it the norm to require PGP use on the job, or is your employer an exception?
If the OP uses PGP for encryption, then his conversation partners use it too, and thus can't use gmail, outlook or yahoo (I am under the impression that desktop outlook has no support for PGP).
Mutt is pretty nice.
Gnome's Evolution was good too, IIRC. There are also Mutt and Pine, but they are terminal clients, so IDK how they handle inline images, tho mutt was OK with html.
HTML email is rendered with w3m which does a decent job.
Searching my local email with notmuch is blazing fast and works even better than Gmail's searching (IMO).
Certainly not everyone's cup of tea but if you like emacs otherwise, it's a great alternative to Gnus. Gnus is originally and primarily a newsreader and treating email like news works in some ways but fails in others. Also searching in Gnus is something I never really got to work well.
Because MH commands aren't part of a monolithic
mail system, you can use them at any time; you
don't have to start or quit the mail agent.
It's fine to mix other UNIX commands between
your MH commands, to leave your mail for a
while and do something else, and to work at
several terminals at the same time. Because
you use MH commands from a shell prompt, you
can use all the power of the shell.
0 - http://rand-mh.sourceforge.net/book/1 - http://rand-mh.sourceforge.net/book/overall/howwor.html#EmaT...
What tool are you using to synchronize with an MTA?
Also, OfflineIMAP[0] looks to be a solid IMAP solution, which may replace my use of fetchmail. However, a maintainer of OfflineIMAP indicates he is focused on imapfw[1]. So maybe that's one to look into as well. It's not that I'm unhappy with fetchmail, but it doesn't hurt to know what the relative strengths and weaknesses are of the choices available.
Like any open source project, the features are all there, but five minutes after installing it I was googling "Thunderbird slow redraw".
I'm not a fan of Thunderbird's aesthetics, but obviously that's subjective.
Functionally, a lot of my problems stem from the Enigmail plugin and Thunderbird search. It really wants encrypted mail to stay encrypted and that means search doesn't work. Last time I looked, there was some hacky workaround with configuring a filter to make a copy of incoming mail and decrypt the copy, but I couldn't get it to work reliably.
IMHO, that's a pretty important add on to keep current.