When enabling Two Factor Authentication for a user in 365 when trying to activate Office for a user the following error display :
Make sure you enable 2fa via : https://www.thecloudjournal.net/2016/10/enable-office-365-modern-authentication/
You need to turn modern authentication on for the User via the Registry :
HKCU\SOFTWARE\Microsoft\Office\15.0\Common\Identity\EnableADAL. REG_DWORD. 1
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