Scenario: You select “ENABLE” on Azure MFA but you do not Enforce. The user has not logged onto Office 365 before and is setting up his Outlook for the first time.

Spoiler warning: Nothing happens, YET.

Here is how Outlook 2016 behaves when you activate Azure MFA for your Account.

1 - mfa on
AZURE MFA portal
2 - fresh outlook 2016
Fresh Outlook boot

3 - add account4 - user entered5 - searching for autodiscover

6 - credential popup
Normal login
7 - enter pwd
standard password
8 - success
success
9 - read email
mail approved