Outlook 2016 and Exchange Online Repeated Credential Prompt

When using Outlook 2016 Professional Plus on Windows 10 (1803) to connect to a synced user's mailbox There is an issue of Repeated Authentication Prompt - It never connects While from the...

outlook

Himanshu Singh
Sep 18, 2018
I was able fix Issue actually there two issues,

1. Oauth was required to be enabled on exchange online at the tenant level (for exchange only) no other application is affected by as the command to do it is an exchange specific commandlet

2. Then there was an additional authentication prompt experienced by the users whose mailbox was migrated to office 365 (EXO) for that there is a registry key
Info about the AllowAdalForNonLyncIndependentOfLync setting in Skype for Business, Lync 2013, and Exchange Online
https://support.microsoft.com/en-in/help/3082803/info-about-the-allowadalfornonlyncindependentoflync-setting-in-skype-f

oryxway

Iron Contributor

Mar 28, 2019

Himanshu Singh

I am having the same issue, but nothing has fixed. As, soon as I start Office 365\Outlook on my Windows 10 desktop, I get the following Windows Security prompt as shown on screen.

I installed this on Windows 10 Desktop which is running on Citrix VDI