Hello @Andre Morais,
Thank you for posting your query on Microsoft Q&A.
Based on your description, you initially tried signing up for Azure using your company email address to register your organization. However, you were unable to create a new tenant because your work or school credentials were already linked to your company's existing directory.
Later, you created a personal Microsoft account and attempted to log into the Azure portal without signing up for a new tenant. However, you encountered authentication errors.
Issue: When users try to log into the Azure portal using a personal Microsoft account (e.g., Outlook, Hotmail), they may receive errors such as: AADSTS160021 or AADSTS16000 or AADSTS50020.
Reason: Whenever you sign in to the Azure portal using a personal Microsoft account, you are automatically connected to the Microsoft Services tenant (f8cdef31-a31e-4b4a-93e4-5f571e91255a).
You can confirm this by nigating to: Azure Active Directory > Overview > Check the Tenant ID (f8cdef31-a31e-4b4a-93e4-5f571e91255a).
In this default tenant, there is no directory associated with your account, which means you cannot perform administrative tasks like creating new users, groups, or enterprise applications. To perform such actions, you need administrative access to a tenant.
Solution: To resolve this issue, you need to create your own Azure tenant instead of using the default Microsoft Services tenant (f8cdef31-a31e-4b4a-93e4-5f571e91255a).
Steps to create a new Azure tenant:
Open an InPrivate/Incognito browser window (to oid Single Sign-On issues). Visit: Azure Free Account Signup to create a new Azure account. When you create a new tenant, you will automatically be assigned the Global Administrator role, granting you full access to all tenant settings and options.I hope this information is helpful. Please feel free to reach out if you he any further questions.
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