RoundCube: DATABASE ERROR: CONNECTION FAILED!

1. Open /var/lib/roundcube/config/db.inc.php or (db.inc.php.dpkg-bak)
and look for the password in the command
$rcmail_config[‘db_dsnw’] = ‘mysql://roundcube:password@localhost/roundcube’;

2. copy that password only

3. Open /etc/roundcube/debian-db.php

4. find $dbpass=’wrongpassword’;

5. Paste to replace ‘wrongpassword’ with the correct password.