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A work or school email is an email address that is managed through Microsoft Entra ID (formerly Azure Active Directory), typically provided by:
A company you work for (e.g., ******@yourcompany.com)
An educational institution (e.g., ******@university.edu)
These accounts are used to access Microsoft services like Teams, Outlook, SharePoint, or enterprise Azure resources. Even if you personally don’t use them for Microsoft services, they may still be registered in Microsoft's business identity system.
The issue is because Microsoft detects that the email domain (e.g., @yourdomain.com) is associated with a business/education tenant, Therefore, Microsoft blocks it from being used for creating a new Microsoft personal account, because such domains are meant to be managed by IT admins.
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