On Sun, Aug 25, 2019 at 09:39:42AM +0200, li...@2ion.de wrote:
> 1st step: Does it happen with other email clients and the same remote
> server? E.g. do use msmtp, Thunderbird etc against the same server for a
> Guess: This looks more like the server / the remote end is shutting the
> TLS connection down. As you know the server and the port, connect with
> openssl s_client a couple of times (it also supports STARTTLS with EHLO,
> though you need to get the exact command from the man page
> openssl-s_client(1)) and speak some SMTP. Perhaps you can reproduce the
> Guess: Could it be that the remote end drops you when under load? Do you
> have access to the remote server logs? If not, your service provider
> might be able to look up potential errors in their log.
Thanks for suggestions, use only if the problem recurrs which it hasn't yet.