> On 2018-12-11, at 17:02, Uwe Brauer wrote:

> Port 465 is SMTPS, while port 587 starts out with plaintext SMTP and
> uses STARTTLS to switch to TLS.  You need to use --starttls with
> gnutls-cli, probably also --crlf:
> gnutls-cli --insecure --crlf --starttls -p 587 mail.gmx.de
> Afterwards, you need to talk SMTP: Type “ehlo localhost”, then
> “starttls”; press ctrl-d to enter TLS mode, which shows crypto
> details.

> I set smtpmail-smtp-server, smtpmail-smtp-service, and
> smtpmail-smtp-user and use ~/.authinfo.gpg for passwords;

Do you really gpg your authinfo file? Where and how do you store its password?