@Yordan Yordanov Users with Hotmail.com, Outlook.com, or other personal email addresses can use Azure MFA even if they don't want to use SSPR.
For example, if guest users with Microsoft Account (MSA) want to access their sign-ins using Security-Info endpoint, they have to register for MFA. They won't be able to use SSPR on that portal to change their passwords but they can leverage Azure MFA to access other features on that portal.
Another case where we might need MFA but not SSPR would be in case of Risky Sign-in by a malicious user. Similarly there may be other scenarios where MFA registration for guests with MSA can help.
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