Hello,
Thank you for posting in Q&A forum.
Security defaults is security measures that Microsoft is enabling by default to enhance security which includes multifactor authentication (MFA) when logging in.
According to the mail, security defaults will be enabled since 2nd, Jan, 2025.
If you would like to disable it, please kindly refer to below Microsoft Official Documentation:
REF: https://learn.microsoft.com/en-us/entra/fundamentals/security-defaults#disabling-security-defaults
I hope the information above is helpful.
If you have any questions or concerns, please feel free to let us know.
Best regards,
Jill Zhou
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