Opening Outlook pops up Windows Security Diagloue wanting me to input credentials

Tom Tirrell 0

Hi,

I'm at my wits end. Outlook all of sudden has started asking me to input the credentials when I open Outlook. I have so far done the following:

Reset password in MS Portal Admin
Reset password in MS Entra
Created a new Outlook Profile
Tried numerous registry changes
I can login via webmail with the authentication details, so I know they're correct
All updates are installed for Windows 11 Pro and Office365
Run both local and online repair of Outlook
The computer is joined using AzureAD so the prompt by default puts in AzureAD<<email address>> with the password prompt.
I have tried combinations with and without AzureAD\ at the front, the name as it appears in the Portal/Entra and also the profile folder path

If anyone can shed some light on what is happening and how I can fix it, it would be much appreciated.

Cheers,

SokiGuo-MSFT 31,026 Reputation points Microsoft External Staff

2025-03-11T07:29:11.5933333+00:00

Hi @Tom Tirrell

Welcome to our forum!

For better research, please provide more details about this case:

What does the password pop-up look like? Please hide your personal privacy information in the screenshot.

What version of your Outlook desktop client is?

Please try to check if the same is happening on another device.
Tom Tirrell 0 Reputation points

2025-03-11T10:36:49.51+00:00

Hi,

Popup attached. It is the lastest version of Outlook client. I can't give you the exact version as Outlook is never able to start due to this error but in Add/Remove Programs it shows Microsoft 365 version 16.0.18526.20144.

It only happens on this device.

I have also run the Microsoft Remote Connectivity Analyzer which gives all green ticks. They are running Windows Security and HP Wolf Security which has not changed. This happens regardless of location (as in at his office or home).

Cheers,

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