Hi!
I have this error working with a fresh installation of RoundCube.
<1bccjbh7> SMTP Error: Connection failed: Invalid response code received from server in /home5/xxxxxx/public_html/correo/program/lib/Roundcube/rcube.php on line 1667 (POST /correo/?_task=mail&_unlock=loading1534863215744&_lang=en&_framed=1&_action=send)
[21-Aug-2018 09:05:16 America/Denver] ERROR: Invalid response code received from server (-1)
Do you know what this mean?
thank you