Experiencing the AADSTS90100 error on Windows 11 can be frustrating, especially when you need to access important Microsoft services. This error usually relates to authentication issues with Azure Active Directory (AAD).
Understanding how to fix this error step-by-step can help you regain access quickly without needing advanced technical skills. This guide will walk you through simple troubleshooting methods to resolve the problem.
Each step is explained clearly, so even if you are new to Windows 11 or Azure AD, you can follow along easily. Let’s get started!
By the end of this guide, you will know how to fix AADSTS90100 and avoid similar errors in the future.
Quick Note: Prerequisites and Initial Checks
Before diving into the troubleshooting steps, consider these quick checks:
- Make sure your internet connection is stable. Authentication requires online access.
- Verify that your Windows 11 system date and time are correct. Incorrect settings can cause authentication errors.
- Confirm you are using the correct username and password for your Microsoft or Azure AD account.
- If you are part of an organization, check with your IT administrator to ensure your account is active and not locked.
Step 1: Check Your System Date and Time Settings
A common cause of AADSTS90100 is incorrect system time or time zone settings. Azure AD uses secure tokens that depend on accurate time synchronization.
To fix this:
- Click the Start button and open Settings.
- Go to Time & language and select Date & time.
- Ensure Set time automatically and Set time zone automatically are turned on.
- If they are already enabled, toggle them off and then back on to refresh the settings.
- Manually correct the time if needed by clicking Edit under “Set the date and time manually”.
After adjusting the time, restart your computer and try signing in again.
Step 2: Clear Cached Credentials on Your Device
Sometimes, outdated or corrupted cached credentials cause authentication failures. Clearing these can help.
Here’s how:
- Open Control Panel by searching for it in the Start menu.
- Navigate to User Accounts > Credential Manager.
- Under Windows Credentials, look for any entries related to Microsoft or Azure AD accounts.
- Click on each relevant entry and select Remove.
- Close the Credential Manager and restart your PC.
- Attempt to sign in again, entering your credentials fresh.
Step 3: Re-register or Reconnect Your Account to Windows
If your account is linked to your Windows profile, it might need to be re-registered or reconnected to resolve the error.
Follow these steps:
- Open Settings and go to Accounts.
- Select Access work or school from the sidebar.
- Find your connected Azure AD or Microsoft account and select it.
- Click Disconnect and confirm.
- Restart your PC.
- Return to Access work or school and click Connect.
- Follow the prompts to sign in with your Microsoft or Azure AD credentials again.
This refreshes your account connection and often clears the error.
Step 4: Check Azure AD Tenant Settings (For IT Admins or Advanced Users)
If you have access to the Azure portal or are an IT administrator, verify that the user account is enabled and correctly configured in Azure Active Directory.
Important checks include:
- Confirm the user is assigned the necessary licenses and permissions.
- Ensure Conditional Access policies are not blocking your sign-in.
- Review sign-in logs in Azure AD to identify any specific error messages.
Adjustments in Azure portal might be required if policies or user settings are causing the error.
Alternative Method: Use the Microsoft Support and Recovery Assistant
Microsoft offers a tool called the Support and Recovery Assistant (SaRA) which can diagnose and fix many sign-in and authentication problems automatically.
To use it:
- Download SaRA from the official Microsoft website.
- Run the tool and select Office or Microsoft 365 sign-in issues.
- Follow the on-screen instructions to let the tool detect and fix problems.
This can save time and effort, especially if you are unsure where the problem lies.
Frequently Asked Questions (FAQs)
What does error AADSTS90100 mean?
This error indicates a problem with authenticating your account against Azure Active Directory. It usually means your device or account is not properly registered or recognized.
Can incorrect time settings cause this error?
Yes. Azure AD relies on synchronized time to validate authentication tokens. Incorrect system time is a common cause of this error.
Is this error related to internet connectivity?
Partially. A stable internet connection is necessary for Azure AD to verify your credentials, but connectivity alone usually does not cause this error.
Do I need admin rights to fix this error?
Most basic fixes do not require admin rights, such as adjusting time settings or clearing cached credentials. However, managing accounts in Azure AD requires administrator access.
Will reinstalling Windows 11 fix the error?
Reinstalling Windows is generally not necessary and should be a last resort after all other troubleshooting steps fail.
When Nothing Works
If you have tried all the above steps and still face the AADSTS90100 error, consider the following options:
- Contact your IT support team: If you are in an organization, your IT department might have policies or restrictions causing the issue.
- Reach out to Microsoft Support: Use the official Microsoft support channels for assistance.
- Check the Microsoft Azure Status page: Sometimes, service outages can cause authentication failures.
- Use the Microsoft Community forums: Other users might have faced similar issues and can offer solutions.
Conclusion
The AADSTS90100 error on Windows 11 is a common but fixable issue related to Azure Active Directory authentication. Starting with simple steps like correcting system time and clearing cached credentials often resolves the problem.
Reconnecting your account to Windows and checking Azure AD settings provide further solutions for more complex cases. Using Microsoft’s automated tools can also simplify troubleshooting.
Remember, staying patient and following the step-by-step guide will help you restore access without stress. If needed, don’t hesitate to reach out for professional support.