Could not connect to the database – check the database connection details you entered and go back and correct them if necessary
On a new WHMCS installation, when you hit the above error message even though you are sure that your MySQL installation is installed correctly – you are able to authenticate via SSH / command prompt with the database credentials as well as from PHPMyAdmin, you should check the configuration.php file to make sure it has the 777 permission as WHMCS required this file to be writeable for installation to proceed to the next steps.
