To use GnuPG with MailCrypt you should

(mc-setversion "gpg")
(setq mc-gpg-user-id "user@foo.dom")

This is all the customization I’ve done to MailCrypt to make it work with GnuPG.

I have been having trouble getting MailCrypt to work on windows, and I didn’t want to depend on cygwin’s sh.exe, so I wrote an independent gpg mode that only requires a working gpg setup: Lisp:dgpg.elDavidElentok

See also