Microsoft 365 Error Codes

How to Fix Microsoft 365 Error AADSTS90019: No Tenant-Identifying Information

Maira Mehtab Sep 20, 2026 869 views

Question details

The user is unable to sign into a new Microsoft 365 account due to an AADSTS90019 error stating that no tenant-identifying information was found in the request.

Product: Microsoft 365
Device & OS: not provided
Scenario: Resetting and attempting to sign into a newly created Microsoft 365 account.
Observed behavior: The system blocks the login attempt every time, displaying error AADSTS90019 because it cannot locate the tenant-identifying information from the credentials.

Before you start

Ensure you have access to an administrator account or can contact your organization's IT administrator, as resolving this backend error requires admin-level support permissions.

Solution 1Recommended

Open a Service Request in Microsoft 365 Admin Center

This is a backend authentication issue that cannot be fixed by user-side troubleshooting. Microsoft Support must investigate and correct the tenant configuration.

Error AADSTS90019 occurs when Azure Active Directory cannot determine which organization (tenant) you belong to based on the sign-in request. Since this is an internal routing or backend sync issue with a newly reset account, it requires direct intervention from the Microsoft Support team.

Log in to the Admin Center

Navigate to the Microsoft 365 admin center at admin.microsoft.com and sign in using a global administrator account.

Access the Help & Support section

Click on 'Support' in the left-hand navigation menu, then select 'Help & support' or 'New service request'.

Submit the support ticket

Provide a brief description of the issue, specifically mentioning 'Error AADSTS90019: No Tenant-Identifying Information found', and submit your request for the backend team to resolve.

If you are not the administrator: If you are a standard user and cannot access the admin center, you must contact your company's IT helpdesk or global administrator to open this ticket on your behalf.

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Frequently Asked Questions

What exactly does Error AADSTS90019 mean?

This error means that Azure Active Directory (the underlying authentication service for Microsoft 365) could not identify your specific organization or tenant based on the login credentials or request URL provided.

Can I fix error AADSTS90019 by clearing my browser cache?

No. While clearing your browser cache can fix many login loop issues, error AADSTS90019 indicates a backend setup or synchronization failure with a new account that only Microsoft Support can resolve.

How do I get help if I am locked out of the Admin Center?

If you are the sole administrator and cannot access the admin center due to this error, you will need to contact Microsoft Business Support by phone using the official support numbers for your country.

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