Microsoft 365 features that help users manage their subscriptions, account settings, and billing information.
Dear KHY,
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Based on the information provided, your scenario is somewhat unusual because the administrator identity is a personal Microsoft account (MSA) rather than a standard Microsoft Entra work/school account.
For an MSA-backed tenant, there is no publicly documented MFA registration endpoint equivalent to aka.ms/mfasetup that allows a personal Microsoft account to satisfy the Microsoft Entra Security Defaults MFA registration requirement.
Security Defaults is an Entra ID feature and is designed around Microsoft Entra work or school identities. If your administrator identity is a personal Microsoft account (MSA), adding Microsoft Authenticator or enabling MFA on the Microsoft account itself does not provide a documented method to complete the Entra MFA registration flow.
Similarly, Security Defaults cannot be turned off without administrative access to the tenant. If all administrator access is already blocked by AADSTS530035, there is no known self-service process to disable Security Defaults from outside the tenant.
In short:
- There is no documented MFA registration endpoint for an MSA-only administrator to satisfy the Security Defaults registration requirement.
- Security Defaults cannot be disabled without first regaining administrative access to the tenant.
- If the tenant is fully locked out, Microsoft Support is generally the only available recovery path.
- You might need to contact Microsoft Support team via phone service number: Customer service phone numbers - Microsoft Support
You might need to contact Microsoft Support team via phone service number: Customer service phone numbers - Microsoft Support
I hope my information meet your expectations, feel free to reach out if you have any other questions.
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