[AzureAD] Fixes MicrosoftDocs/azure-docs#49269

Author: iainfoulds

articles/active-directory/authentication/howto-mfa-nps-extension.md

@@ -140,6 +140,14 @@ Use these steps to get a test account started:
 2. Follow the prompts to set up a verification method.
 3. [Create a Conditional Access policy](howto-mfa-getstarted.md#create-conditional-access-policy) to require multi-factor authentication for the test account.
 
+> [!IMPORTANT]
+>
+> Make sure that users have successfully registered for Azure Multi-Factor Authentication. If users have previously only registered for self-service password reset (SSPR), *StrongAuthenticationMethods* is enabled for their account. Azure Multi-Factor Authentication is enforced when *StrongAuthenticationMethods* is configured, even if the user only registered for SSPR.
+>
+> Combined security registration can be enabled that configures SSPR and Azure Multi-Factor Authentication at the same time. For more information, see [Enable combined security information registration in Azure Active Directory](howto-registration-mfa-sspr-combined.md).
+>
+> You can also [force users to re-register authentication methods](howto-mfa-userdevicesettings.md#manage-user-authentication-options) if they previously only enabled SSPR.
+
 ## Install the NPS extension
 
 > [!IMPORTANT]