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To grant a user access to the FusionAuth admin UI, you need to:

Create the user in the Default tenant (not a custom tenant) Register them for the FusionAuth application (the built-in admin application) Assign them an appropriate admin role during registration (e.g. "admin" for full access or a more limited role)

The key distinction is that the Tenant Manager Application is intended for granting third-party users limited admin access to manage users and identity providers within a specific tenant (this is an Enterprise feature). For full admin UI access, you must use the FusionAuth application in the Default tenant.

If the user's password setup email is being filtered as spam, you can set a temporary password manually and they'll be prompted to change it on first login.

Steps to add an admin user: Navigate to Users in the Default tenant Create a new user or select an existing one Go to the Registrations tab Click Add registration Select the FusionAuth application Choose the appropriate admin role from the dropdown Save the registration Available Admin Roles

Here are the main admin UI roles you can assign:

Role Description admin Can manage everything, including creating new users with administrator privileges user_support_manager Limited scope — recommended for tier 1 support staff user_support_viewer Can view user information only user_manager Can add and edit users (note: this role has similar power to admin, so use user_support_manager for restricted access) user_deleter Can delete users

Important: A user must have a registration in the FusionAuth application to access the admin UI — group membership alone is not sufficient.

Related Documentation FusionAuth Admin UI Roles - Complete list of admin roles and their capabilities User Support Guide - Detailed guide on creating admin users Default Tenant - Why the Default tenant cannot be deleted and its relationship to the FusionAuth application Tenant Manager Application - Enterprise feature for providing limited admin access to third-party users within specific tenants