Microsoft MFA Prompt when connecting school account in Windows

[kcoxeverhart]

For reference I'm talking about ( Windows under settings -> Accounts > Connect a work or school account)

When our users choose to connect their school or work account they are getting both our DUO MFA that is configured with conditional access, and the Microsoft MFA prompts.  We don't use Microsoft MFA, it's not enabled in conditional access, and it's not enabled in our Intune device management.  How do we stop the Microsoft MFA prompt so the user is only getting the single DUO MFA prompt?

[#2]

@kcoxeverhart 

How about security defaults? Did you enable recently?

Security defaults and Conditional Access - Microsoft 365 Business Premium | Microsoft Learn

[#3 · Accepted solution]

That was a good thought, I checked this morning, and the security defaults are showing as disabled. I went into our conditional access policy for our DUO MFA and told it to not apply to Intune and Intune initial registration. But our users are still getting both Microsoft MFA and DUO MFA when logging in. That says to me, it's not coming from Intune registration either. I'm going to keep looking to see if I can figure out what's prompting it.

[#4]

I finally figured out this. It's being caused by Intune Hello for Business. One of our admins had recently turned this on to test out biometric authentication, and as a result it was prompting for MFA.