My account shows a separate email domain address which do I use for Microsoft 365

Question

A few months ago my free subscription expired and I was helped by a person contacted via phone, he guided me to set up a separate account domain name and subscribed for Microsoft 365 Basic (no Teams). My recurring payments have stopped because my credit card has changed number. I am now unable to login to the separate account he said to login to and purchase the 365 subscription. I am unable to create the separate email domain on the Microsoft Authenticator App. Do I need the separate domain account under my primary email address account, should it be removed somehow?

Answer 1

Hi, glad to assist you today.

The name301.onmicrosoft.com address is your Microsoft 365 work account, and you must sign in with that exact username, not your personal email. If Microsoft Authenticator only asks for a code and does not show one, the correct account is likely not added in the app. Try password reset at https://passwordreset.microsoftonline.com using the onmicrosoft.com address.

If reset fails, only Microsoft 365 Support can verify the tenant and restore access, since Community members do not have access to accounts. When you try to sign in, do you receive a password error or a verification prompt?

Answer 2

The separate domain is ******@name301.onmicrosoft.com, I don't have any other user name for access. On the website is says to open the authenticator app, but the app only asks for a code it does not give a code.

Answer 3

The separate address is a normal part of a Microsoft 365 subscription and does not usually need to be removed. When a Microsoft 365 for business–type subscription is created, an initial domain like yourname.onmicrosoft.com (or a regional variant such as partner.onmschina.cn) is created automatically and used for the account’s user ID and email unless a custom domain is added later.

Key points for this situation:

1. Which address to sign in with
   • The user ID for the Microsoft 365 subscription is typically in the form ******@something.onmicrosoft.com or ******@yourcustomdomain.com.
   • The “separate domain” account is likely this Microsoft 365 user ID. That is the address that should be used to sign in to manage the Microsoft 365 subscription and payments, not the personal email alias.
   • If the custom domain was added, the sign-in ID might now be the custom-domain address instead of the original onmicrosoft.com address.
2. Why there is a “separate” domain
   • For Microsoft 365 for business, each user gets a unique user ID that includes the tenant’s domain, for example ******@fourthcoffee.onmicrosoft.com or ******@fourthcoffee.com after adding a custom domain.
   • This is required for the subscription and is separate from any personal Microsoft account that might use the same primary email address.
3. Relationship to Microsoft Authenticator
   • The Authenticator app does not create or own the domain; it only holds sign-in methods for accounts.
   • If the phone was changed or the Authenticator entry was removed, the account must be recovered using alternate verification methods (such as an alternate email address) or with Microsoft support. The domain itself does not need to be recreated in Authenticator.
4. Whether the separate domain account should be removed
   • The domain-based account is the core identity for the Microsoft 365 subscription and normally should not be removed if the subscription is still needed.
   • Removing the domain or account would break access to the subscription and any associated services.
5. How to regain access and update payment
   • Use the Microsoft 365 user ID (for example, ******@yourtenant.onmicrosoft.com or ******@yourcustomdomain.com) to sign in.
   • If the user ID has been forgotten, check the original welcome/introductory email that was sent to the alternate email address when the subscription was first set up; it contains the user ID and sign-in URL.
   • If sign-in is blocked because of lost Authenticator and there is no other admin in the tenant, contact Microsoft support so the Data Protection team can verify identity and help regain access to the administrator account, then update the payment method.

In summary, the separate domain account is required for the Microsoft 365 subscription and should not be removed; instead, focus on recovering access to that account and then updating the payment details.

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References:

• What is my user ID and why do I need it for Office 365 for business?
• What is my user ID and why do I need it?
• Change your Microsoft 365 email address to use your custom domain
• Overview
• I have a Micrsoft business account and I am the admin and the only user registered under this account. I can't log in because i have replaced my phone and the authenticator doesn't work. - Microsoft Q&A