Link Here: Outlook (365) Need Password - Issue - Microsoft Community Hub

Cannot get Outlook e-mail from O365. Error is Need Password.

Solution: Update Registry Key: Computer\HKEY_CURRENT_USER\SOFTWARE\Microsoft\Office\16.0\Common\Identity\DisableWinHttpCertAuth to 1

If this is ok, setting the below registry key to 1 in below path often resolves it:
Path: HKEY_CURRENT_USER\Software\Microsoft\Office\16.0\Common\Identity
Key: DisableADALatopWAMOverride (DWORD)