Microsoft seems to be obliging its 0365 customers to use the Microsoft MFA from October 15, 2024

[Laurent_TERUIN_MVP]

https://workingtogether.fun/2024/08/27/microsoft-semble-obliger-ses-clients-0365-dutiliser-le-mfa-mi...

If you’re a Tenant Office 365 administrator, you must have received this kind of message warning you that MFA activation for all users will be mandatory from October 15, 2024 or, if you’ve postponed it, from March 15, 2025. This MFa will be required for all users needing to access the following resources (the Azure portal, Microsoft Entra admin center, and Intune admin center)

Personally, I’m in favor of this for obvious security reasons. However, activating MFA for all users implicitly means asking them to use either their personal email addresses, or to install an authentication application (Microsoft Authenticator or Google Authenticator) on their phone (business or personal), or even to enter their phone number (business or personal) to receive the SMS.

This obviously requires a bit of communication and education to get everyone on board. On the other hand, it poses another problem for organizations that have chosen not to use Microsoft’s MFA solution. What will happen on March 15, 2025 for those organizations that have activated MFA via a third-party solution

Microsoft had already automatically pushed conditional access rules that could be deactivated, 

Will these rules be automatically activated on March 15, 2025?
Will the use of Microsoft MFA become mandatory to the detriment of other solutions?
All this information is not provided in the message you received.

[#2]

Hello,

You can nudge users to set up Microsoft Authenticator during sign-in. Users go through their regular sign-in, perform multifactor authentication as usual, and then get prompted to set up Microsoft Authenticator. This allows targeted campaigns to move users from less secure authentication methods to Authenticator.

As per the external authentication methods, yes some companies have the need to utilize 3rd party tools, hence Microsoft Custom Control (Preview). Custom controls are a preview capability of the Microsoft Entra ID. When using custom controls, your users are redirected to a compatible service to satisfy authentication requirements outside of Microsoft Entra ID. To satisfy this control, a user's browser is redirected to the external service, performs any required authentication, and is then redirected back to Microsoft Entra ID.