Hi @Septovan · Thank you for reaching out.
As of now, Security Defaults can either be enabled or disabled. When enabled, Security Default requires all users to register for Azure AD Multi-Factor Authentication. You cannot configure Security Defaults to select specific set of users to require MFA or exclude a set of users from security defaults.
Since Security Defaults is available as a free feature with Azure AD Free edition, it does not include any configuration options. Unfortunately, as of now, to configure exclusions, you will need to Conditional Access which requires Azure AD Premium P1/P2.
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