Microsoft 365 Business Standard – Sole administrator locked out after losing Authenticator access

Milivoje Neskovic 0 Reputation points
2026-10-17T16:16:57.19+00:00

Hello,

I am the owner and sole administrator of a small company in Norway with an active Microsoft 365 Business Standard subscription, purchased directly from Microsoft.

After replacing my Samsung S25 Ultra with a Samsung S26 Ultra, I lost access to Microsoft Authenticator for my Microsoft 365 administrator account.

My password is correct, but Microsoft requires either approval through the previous Authenticator registration or a six-digit verification code.

The account is no longer correctly registered in Authenticator on my new phone. Therefore, I cannot access the Microsoft 365 Admin Center or register a new authentication method.

I have already attempted to contact Microsoft Support by telephone and e-mail, but I have not been able to open a new support case for this account.

I need assistance with:

Opening an official Microsoft 365 Data Protection / Tenant Recovery support case.

Resetting the previous MFA registration.

Registering Microsoft Authenticator again on my Samsung S26 Ultra.

Restoring administrator access to my existing Microsoft 365 Business Standard subscription.

I can provide subscription invoices, proof of payment and company ownership through an official secure Microsoft support channel.

Could a Microsoft moderator please explain how to reach the Data Protection team and open a new support case when the sole administrator cannot access the Admin Center?

Thank you for your assistance.

Microsoft 365 and Office | Subscription, account, billing | For business | Other
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2 answers

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  1. Jack-Bu 7,045 Reputation points Microsoft External Staff Moderator
    2026-10-17T17:25:42.1166667+00:00

    Hello Milivoje,

    if you're the only Global admin, you will need to contact Data Protection team. They can help you regain access to your tenant.

    Please note that this forum is not Microsoft support, this is a user-to-user support forum. Therefore, I cannot directly escalate this for you. However, I can guide you how to contact Data Protection team.

    First, you can try phone support with the script below. Please visit the following page and reach out to phone number via: Customer service phone numbers - Microsoft Support

    From what I know, you will need to get past the initial AI system to reach the live support team. You can refer to the guide below for tips on how to get through more easily:

    User's image

    it's not working, please follow this link to create a trial tenant: https://www.microsoft.com/microsoft-365/business/microsoft-365-business-basic?msockid=3eb6980b5c6860e63a588d0c5d1761d6 - after that you will be able to access to Microsoft 365 Admin Center to raise the ticket

    Assuming that you have already created an account after registering a free trial and you can go to Microsoft 365 admin center and click "Help & support" icon to raise your ticket.   

    User's image

    Please mention that you are raising ticket on behalf of the affected tenant that you do not have access to.

    Important note: if you do create the trial and it resolves the issue, please remember to cancel the subscription afterward to avoid any related charges. 


    Note: Please follow the steps in [our documentation] to enable e-mail notifications if you want to receive the related email notification for this thread.

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  2. AI answer

    2026-10-17T16:17:52.4933333+00:00

    Because no second administrator or alternative authentication method exists, call Microsoft’s Norway business-support number and request a tenant-lockout case escalated to the Data Protection/Tenant Recovery team.

    Open the recovery case

    Microsoft lists these Norway work-account support numbers:

    • 800 62002 — toll-free
    • 23 500 500 — toll call

    These numbers are listed on Microsoft’s official work-account support page.^1^

    Since the previous telephone and email attempts did not produce a case, use this specific description with the telephone agent or automated system:

    “This is a Microsoft 365 Business tenant lockout. I am the sole Global Administrator, my password is known, but the only registered Microsoft Authenticator method is unavailable. There is no second administrator and no alternative MFA method. I need a service request escalated to the Data Protection/Tenant Recovery team for tenant ownership verification and MFA recovery.”

    For the automated prompts, the matching route reported for this scenario is:

    1. Select business email user.
    2. Select technical help.
    3. Problem: Authenticator.
    4. Product: Office 365 for business.
    5. Account type: company.
    6. Administrator: Yes.
    7. Other administrators: No.
    8. Request: Create a service request and escalate it to the Data Protection Team.^2^

    Ask the agent to provide the case number before the call ends. A Q&A moderator cannot directly reset MFA; the recovery team must verify tenant ownership and handle the locked-out administrator account.

    Prepare for ownership verification

    Have the following ready:

    • Tenant name and, if known, tenant ID
    • Locked-out Global Administrator username
    • Company’s registered name and business information
    • Custom domain and evidence that the company controls it
    • Microsoft 365 subscription invoices and billing details
    • Payment information requested by Support
    • Telephone number and an alternate email address that you can currently access

    Provide invoices, payment information, and identity documents only through the secure channel specified in the official support case. These are among the details used in comparable tenant-recovery cases.^3^

    Reset and register Authenticator again

    After ownership verification, ask the recovery team to require MFA re-registration for the Global Administrator. Microsoft documents that this action removes registered phone numbers, Microsoft Authenticator registrations, and software OATH tokens; the user is then prompted to configure a new MFA method at the next sign-in.^4^

    Once Support confirms recovery:

    1. Install or open Microsoft Authenticator on the Samsung S26 Ultra.
    2. Sign in to Microsoft 365 with the restored administrator account.
    3. At the security-information prompt, select Microsoft Authenticator.
    4. In Authenticator, select Add account → Work or school account → Scan QR code.
    5. Scan the QR code displayed by Microsoft 365.
    6. Complete the test notification or verification-code prompt.
    7. Finish registration and confirm that the new method appears in My Profile → Security info.

    Microsoft’s setup procedure confirms that the new verification method is saved after the registration and verification process completes.^5^

    Do not delete the existing tenant, cancel the subscription, or create a replacement subscription while recovery is in progress; those actions do not recover the existing tenant’s administrator access.

    After access is restored, add another appropriately protected administrator account and register more than one permitted authentication method to avoid another single-administrator lockout.


    References

    1. [Work account](https://support.microsoft.com/support/#technical-or-sales-support-phone-numbers)
    2. Sole Global Administrator Locked Out – Lost Microsoft Authenticator Access After New Phone - Microsoft Q&A
    3. Sole Global Administrator locked out due to unavailable MFA – no other admin in Microsoft 365 tenant - Microsoft Q&A
    4. Manage user authentication methods for Microsoft Entra multifactor authentication
    5. Set up multifactor authentication for your Microsoft 365 account | Microsoft Support
    AI-generated content may be incorrect. Read our transparency notes for more information.

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