Outlook “Need Password” With No Prompt – Office 365 Multifactor Authentication

After migrating mailboxes from on-premise Exchange 2013 to Office 365, some Microsoft Outlook 2016/2019/Office 365 clients kept on getting a message on the bottom right-hand corner of Outlook saying “Need Password” without being prompted to enter it, they would click on the message and it would disappear, and Outlook would resume receiving emails but after a little time that message would come up again.. this behavior continues persistently through the day…

Modern Authentication is enabled and might have contributed to the issue.

1- The following registry keys fixed the issue (Close Outlook and other MS programs before making changes).  Reboot computer after making changes.  Add as DWORD and set to 1.  You can save it to a reg file and double-click to add the keys automatically:

Windows Registry Editor Version 5.00

[HKEY_CURRENT_USER\SOFTWARE\Microsoft\Office\16.0\Common\Identity]
“Version”=dword:00000001
“EnableADAL”=dword:00000001
“DisableADALatopWAMOverride”=dword:00000001
“DisableAADWAM”=dword:00000001

 

2- Now browse to the following registry location:

HKEY_CURRENT_USER\Software\Microsoft\Office\16.0\Outlook\AutoDiscover

Find out if the following DWORD exists

ExcludeExplicitO365Endpoint”

and if it does delete it.

3- Reboot your the computer after that.