Microsoft 365 Global Administrator Locked Out – MFA Phone Number Belongs to Former/Unknown Administrator

Question

Our organization is currently trying to regain administrative access to our Microsoft 365 tenant after our previous IT administrator left the organization.

We have access to the Global Administrator username and password, and the credentials are working successfully. However, when we sign in, Microsoft requires MFA verification.

The available verification methods are:

• Microsoft Authenticator, which we cannot access because it was configured on the former administrator's device.
• An alternate phone number that is not known or controlled by anyone currently at our organization.

We selected “I can't use my Authenticator app right now,” but Microsoft simply takes us back to the same verification screen. We also tried the normal Microsoft 365 support option, but it requires us to already be an administrator, which is the problem we are trying to resolve.

At this point, we appear to have no accessible Global Administrator account for the tenant.

We are the current organization and domain owner and can provide documentation to verify our organization's identity and ownership of the Microsoft 365 tenant/domain.

What is the correct process for recovering the Global Administrator account and replacing the inaccessible MFA methods?

Specifically, how can we open a support case or reach Microsoft's Data Protection/Tenant Recovery team when we cannot complete MFA and therefore cannot access the Microsoft 365 Admin Center?

We are not looking to bypass Microsoft's security requirements. We are trying to complete the appropriate ownership verification and legitimate tenant recovery process.

Any guidance from Microsoft moderators or others who have successfully recovered an orphaned Microsoft 365 tenant would be greatly appreciated.

Answer 1

Dear @Magali M

You can contact the Microsoft Data Protection Team using the following link and the methods described above: https://support.microsoft.com/en-us/support/

Some countries, the call may be handled by an automated conversation. For example:

1. What kind of problem are you concerned about?
   1. Authenticator
2. What kind of product are you using?
   1. Office 365 for business/Azure portal/Entra ID
3. Is this an education or company account?
   1. Company
4. Are you an administrator?
   1. Yes
5. Do you have another administrator in your organization?
   1. No
6. You need to create a service request
   1. Yes

Once you reach a support engineer, I would be very explicit:

“This is a Microsoft Entra tenant lockout. The only Global Administrator account is no longer accessible, and there are no other Global Administrators in the tenant. We need to recover administrative access to the tenant. Please escalate this case to the Data Protection / Tenant Recovery team.”

Have the following information ready for the ownership verification:

• Tenant ID
• Initial *.onmicrosoft.com domain
• Microsoft 365 subscription and billing information
• Company information
• Details about the previous Global Administrator
• Any other information Microsoft requests to verify ownership

Other option would be to create a temporary Microsoft 365 tenant using a trial subscription. You can then use this tenant to access the Microsoft 365 Admin Center and contact Microsoft Support. Once the new tenant is set up, sign in to the Microsoft 365 Admin Center and go to Support › Help & Support. Open a new support request and explain that you need help recovering access to your original tenant. In the request, mention that you are the Global Administrator of the original tenant and that you are currently locked out because you no longer have access to the MFA method required to sign in. One important thing: the trial tenant is only needed to contact Microsoft Support. After you regain access to your original tenant and the issue has been resolved, remember to CANCEL the trial subscription so you don't accidentally get charged.

Microsoft's instructions for cancelling a trial subscription can be found here: https://learn.microsoft.com/en-us/microsoft-365/commerce/subscriptions/cancel-your-subscription?view=o365-worldwide&#how-do-i-cancel-my-free-trial

I hope this helps.

Best regards,

Bence