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If you are logged in as the superuser admin you must first click the Manage Tenants link to display the list of tenants. Then click the 
button to manage users/roles for the desired tenant. Then click the Manage Users link. The superuser admin can add users to the special d (default tenant) users . New Users added to the default tenat can only be new superuser adminswill become new superusers. This allows you to name additional superusers and if you want you can disable the built-in superuser named "admin". To disable the build-it superuser named "admin" click the 
button above the alpabet list. This brings you directly to the build-in superuser admin's edit page, or you can click the icon to the right of the admin name in the user list. Set the Enabled dropdown to false. This will prevent further logins by the built-in superuser named "admin". Note you cannot delete the built-in superuser named "admin". You can however delete any additional admin user you have created.
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