No puedo acceder a mi tenant de Azure/Entra ID (AADSTS90100 y AADSTS160021)

Pau R Error AADSTS160021 is thrown when the user not found in the tenant used for authentication. In your case, this error usually occurs when you sign in to Azure Portal using your personal account which is not added as an external/guest user to an Azure AD tenant. Due to this, you by default get connected to the Microsoft Services tenant.

Since you are connected to the Microsoft Services tenant as a standard user with restricted access, 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.

For this purpose, you need to create your own tenant rather than using the Microsoft Services tenant. 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.

To create a new tenant, open in-private/incognito browser window (just to avoid SSO), access Create Your Azure Free Account Or Pay As You Go | Microsoft Azure to create a free Azure account.

In some cases, the user might already have an active session that uses a different personal account than the one that's intended to be used. Or they have a session that uses their organization account although they intended to use a personal guest account (or vice versa).

In that scenario, try signing in to the Azure Portal trough a tenant-specific URL using the following fo

[https://portal.azure.com/<tenant] domain name>

Eg.

https://portal.azure.com/constoso.onmicrosoft.com

Hola,

Me parece que si eres el único Administrador Global y no puedes iniciar sesión, solo el soporte interno de Microsoft puede resolver tu problemática.

Para ello, puedes crear un ticket de soporte de Azure sin iniciar sesión: https://azure.microsoft.com/es-es/support/create-ticket

Un saludo.