In some circumstances, you may find that RoundCube loads up with the following error message:
DATABASE ERROR: CONNECTION FAILED!
Unable to connect to the database!
Please contact your server-administrator.
When attempting to locate the RoundCube database in /home/$user/etc/$domain, the databases are not present.
The issue is most often caused by the cPanel PHP-FPM process hanging onto connections. Sending PHP-FPM a hard-restart generally addresses the problem.
To restart the process, we recommend: