error 451

[simoneitalia]

Hello to everyone!
i'm new to roundcube, but i like very much.
I install the app on my server and i have a little problem. I can send email to all over the world but not do the domain on my server. I receive that  Error

Errore SMTP (451): inserimento del destinatario "[email protected]" non riuscito (4.3.5 Server configuration error)
SMTP error (451): insertion of the recipient "[email protected]" failed (4.3.5 Server configuration error)

this is my config file

$config['smtp_server'] = 'tls://qsr33802.myservfer.com';
$config['smtp_port'] = 587;
$config['smtp_auth_type'] = 'LOGIN';
$config['smtp_user'] = '';
$config['smtp_pass'] = '';

Thanx for your time and collaboration.

Simone

[JohnDoh]

your SMTP server reported "4.3.5 Server configuration error" so the issue lies there.