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In a Sign-in Risk Conditional Access Policy, blocking access outright might not always be the best approach. Instead, requiring Multi-Factor Authentication (MFA) is often the recommended approach.
Block Access might lead to a False positive (as it's AI-based signals), and it does not give the better user experience to verify their identity whereas MFA provides the user the ability to verify their identity.
So, blocking access in a Sign-in Risk policy is not necessarily "wrong," but requiring MFA is a better and more flexible security measure in most cases.
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