Need to reset Teams Trial tenant (created by another admin, he works with me but has given up)

Dear @Eddie Fong, 

Thank you again for reaching out and for keeping me updated on your situation.  

• If the tenant was deleted by the other admin, it is only fully removed after Microsoft completes its deletion checks. These checks ensure there are no remaining users, applications, or Microsoft 365 or Azure subscriptions.
• Canceling or letting a trial expire does not delete the tenant. License based subscriptions must be fully removed and reach the Deprovisioned state before tenant deletion can be completed.
• Usually, the onmicrosoft.com name becomes available once the tenant is fully deleted. If the name is still unavailable, it likely means the deletion is not finished yet, or backend references are still being cleared.

Please consider the following options:

Option 1: Confirm the old tenant is fully deleted

If the other admin can still sign in, I recommend following the tenant deletion steps in the Entra admin center and confirming that no subscriptions or applications are blocking deletion: Delete a Microsoft Entra tenant - Microsoft Entra ID | Microsoft Learn

Option 2: Continue now with a temporary tenant name

If you need to move forward immediately, you can create a new tenant with a temporary onmicrosoft.com name. Once your preferred name becomes available, it can be added as an additional onmicrosoft.com fallback domain and then set as the fallback domain.

Please note that onmicrosoft.com domains cannot be removed after creation, so it is best to double check the spelling first.

This article provides further guidance on the topic: Add or replace a onmicrosoft.com fallback domain - Microsoft 365 admin | Microsoft Learn

Option 3: Contact Microsoft Support if the name is urgent

If the tenant's name is still unavailable and urgently needed, opening a Microsoft Support request is the best way to check the backend status. After creating a new tenant, you can submit a ticket through Microsoft 365 Admin Center > Support > Help & Support.

I hope this information helps clarify your concerns and supports you in moving forward with confidence.

Dear @Eddie Fong, 

Thank you for sharing your concern. 

Based on the information you’ve provided, I’d like to clarify the current situation and outline the options available to you. 

Just to gently clarify before we go any further, this is a user‑to‑user support forum. I don’t have the ability to access or investigate individual accounts because this is a user-to-user support forum. Moderators and contributors, including external Microsoft employees, do not have access to internal systems or the ability to directly take action on Microsoft product features. However, I’m more than happy to help review your situation and guide you toward the appropriate next steps.

Since your Gmail address was added to an existing tenant, your account is classified as a guest user. At this time, Microsoft does not support fully “resetting” a tenant or transferring tenant ownership to a guest account. Administrative access can only be assigned to an account that is part of the tenant’s native domain, such as ******@companyname.com or yourname@companyname.onmicrosoft.com_. 

To move forward, one of the following approaches would be necessary: 

Option 1: Contact the former admin to grant admin access 

If it is still possible to contact the former admin, this is the most direct option. 

Ask the former admin to sign in to the Microsoft 365 admin center using their admin account. 

Have them either:  

• Assign Global Administrator access to an existing tenant account, or 
• Create a new user account in the tenant using the tenant domain and assign that account the Global Administrator role. 

Once Global Administrator access is available to you, sign in to the Microsoft 365 admin center. 

From there, you can update account details, reset passwords and manage Teams settings as needed. 

This option allows you to continue using the existing tenant without starting over. 

Option 2: Create a new tenant under your own control 

If the former admin cannot be reached or is unable to assist, creating a new tenant is the cleanest solution. 

Sign up for Microsoft 365 subscription using your personal email address. 

Complete the signup process. 

After signup, you will receive an email containing:  

• The new tenant’s admin account, such as ******@company.onmicrosoft.com. 
• A temporary password and subscription confirmation. 

Sign in to the Microsoft 365 admin center using this new admin account. 

Change the password and proceed to configure Teams from the beginning with full admin control. 

This option ensures you are the Global Administrator from day one and avoids any dependency on the previous setup. 

• About the existing Teams Trial tenant 

If the old trial is linked to a payment method, it should be cancelled to avoid any unintended charges. 

Note: In most cases, the trial is tied to the person who originally signed up, including their payment details. If you did not enter your card information for that tenant, no charges should apply to you. 

If the former admin needs to cancel the trial, they can do so using these steps: 

• Sign in to the Microsoft 365 admin center > Go to Billing > Select Your products. 
• Choose the Microsoft Teams trial > Edit recurring billing and turn it off. 

I hope this information is helpful. If you have any questions or need further support, please don’t hesitate to reach out at any time.  

Thank you for your patience and understanding.  

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