Recently while trying to install roundcube I am stuck with the error “roundcube SMTP Error (250): Authentication failed”.
With the error the clear hint is there should be some issue with SMTP setting, so I checked all SMTP settings and I had bit doubt on following settings.
$rcmail_config['smtp_user'] = '%u'; $rcmail_config['smtp_pass'] = '%p';
After doing some experiments with my main.inc.php file following tweaks are worked for me.
$rcmail_config['smtp_user'] = ''; $rcmail_config['smtp_pass'] = '';