Forum Discussion
Microsoft Outlook Credential Popup Hidden / Blank on Entra ID–Joined Devices
Hello Community,
I am encountering a persistent issue with Microsoft Outlook on Entra ID (Azure AD)–joined devices. Users are repeatedly prompted for credentials, but the popup does not display properly — it appears as a tiny, mostly blank window (see attached screenshot) and is sometimes only visible in Task Manager. As a result, users cannot complete the login process.
Environment & Observations:
-Devices are fully Entra ID joined.
-Users have valid Microsoft 365 licenses.
-The popup appears as a small, blank, non-interactive window.
-Clearing cached credentials and re-registering Microsoft Accounts / WAM components did not resolve the issue.
-Registry value WamDefaultSet shows YES.
-More common on fully Azure AD–joined devices
Troubleshooting Steps Already Attempted:
-Cleared cached credentials in Windows Credential Manager.
-Re-registered Microsoft Account / WAM components.
-Verified user accounts and M365 license assignments.
-Checked network connectivity and device compliance.
Questions / Guidance Requested:
Is this a known issue with Outlook credential popups on Entra ID–joined devices?
Are there registry tweaks, Intune policies, or configuration changes that can ensure the popup renders correctly?
Could this be related to Conditional Access, SSO, or token handling in Entra ID?
Any insights or solutions would be greatly appreciated.
2 Replies
I have the same problem. Tried everything possible except reinstalling windows. In a new account the problem also persists, so it's not account related but a more global problem.
This issue with the blank or tiny Outlook credential popup on Entra ID–joined devices is actually fairly common and usually linked to how Windows handles modern authentication through the Web Account Manager (WAM). It often means the sign-in component has become misconfigured or cached incorrectly. The easiest fixes are to remove and re-add the work account under Settings → Accounts → Access work or school, clear any Microsoft-related credentials in Credential Manager, and make sure the device is still properly joined to Entra ID by running dsregcmd /status. You can also try signing out of all Office apps, restarting, and signing back in, or doing an online repair of Microsoft 365. If the issue persists, it might be tied to Conditional Access or token policies, so checking those in Entra ID or Intune can help too. It’s not dangerous, just a frustrating authentication glitch that usually clears up once WAM or the cached credentials are refreshed.
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