Hello @규철 조 ,
I Understand that you are getting Interaction required: AADSTS160021: Application requested a user session which does not exist.
When you try to log in to Microsoft Entra ID by using your personal Microsoft Accounts (Outlook, Hotmail or OneDrive), you are connected to the Microsoft Services tenant by default. Within the default tenant, there is no linked directory for performing any actions. This behavior is expected.
As this is a standard tenant without any directory associated, you cannot perform actions such as creating new users, groups, enterprise applications, and so on. To perform administrative actions, you must have administrative access to the tenant.
Solution: For this purpose, you need to create your own tenant rather than using the Microsoft Services tenant.
To create a new tenant, open in-private/incognito browser window (just to avoid SSO), access https://azure.microsoft.com/en-us/free/ to create a free Azure account.
When you create a new tenant, you by default become the Global Administrator of the new tenant and have full access to all the options in that tenant.
If you still want to access Entra portal using your personal Microsoft account only, you can invite that user as a guest user as mentioned here : https://learn.microsoft.com/en-us/azure/active-directory/external-identities/add-users-administrator#add-guest-users-to-the-directory and assign the Global Administrator role.
Hope this helps. Do let us know if you any further queries.
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