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To create an unlicensed "application user" in your environment, follow these steps. This application user will be given access to your environment's data on behalf of the end user who is using your application.
1.Navigate to your Dataverse environment (https://[org].crm.dynamics.com).
2. Navigate to Settings > Security > Users.
3. Choose Application Users in the view filter.
4. Select + New.
5. In the Application User form, enter the required information.
6. In the Application ID field, enter the application ID of the app you registered earlier in Azure AD.
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7. After selecting SAVE, if all goes well, the User Name, Application ID URI, Azure AD Object Id, Full Name, and Primary Email fields will auto-populate with correct values where:
User Name == 'Application Name + Application ID'@TenantID.com
Full Name == 'Application Name'
Primary Email == User Name
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8. Before exiting the user form, choose MANAGE ROLES and assign a security role to this application user so that the application user can access the desired organization data.