The first person to log in to CAST Imaging following authentication configuration (or when changing the authentication mode) will be confronted with the following message - this indicates that the user that has logged in is not permitted to access any data and that there are no users with the SUPER ADMIN role:

The first step to resolve this is to assign one user the SUPER ADMIN role which has permission to access all data, configuration settings and tenants. To do so and assuming that the current logged in user should be granted the SUPER ADMIN role, click the settings button highlighted below:

The following message will then be displayed (this message is displayed when the system detects that there are no users that have been granted the SUPER ADMIN role):

Clicking the BECOME SUPER ADMIN button will grant the SUPER ADMIN role to the currently logged in user and then Admin Center will be displayed. You should then proceed with Configure a license key.