Hi there After upgrading my Debian 8 to 9 I have issues with postfix: I can login fine. I can send email fine from horde/roundcube. But I can't send any email from thunderbird. Thunderbird returns: Code: Sending of the message failed. The message could not be sent using Outgoing server (SMTP) xxx for an unknown reason. Please verify that your Outgoing server (SMTP) settings are correct and try again. And the mail log has: Code: SSL_accept error from xxxx[10.10.10.19]: -1 warning: TLS library problem: error:1417A0C1:SSL routines:tls_post_process_client_hello:no shared cipher:../ssl/statem/statem_srvr.c:1404: I reconfigured services but it just won't work.