Azure SSO is providing blank screen for multiple platforms

Question

Azure SSO is providing blank screen for multiple platforms

Jackie 0

Our company uses Azure (Entra ID) for SSO across multiple platforms. Recently, we’ve started experiencing the same issue across several different systems:

User logs in via Azure SSO successfully

Credentials are accepted

When attempting to complete an electronic signature inside the platform (re-auth prompt), the Azure password screen loads

After entering the password, the SSO window goes completely blank

No error message. Just a white/blank screen. This is an intermittent issue

This is happening across multiple vendors/platforms, which makes me suspect this is not app-specific. One of our vendors mentioned this may be related to a relatively recent Microsoft/Azure update affecting SSO redirect/token behavior.

A few additional details:

Happens in multiple browsers

Not limited to a single platform

Initial login works fine , issue only occurs during signature re-auth
Appears to be failing post-password entry

Appreciate any direction. Thank you

VEMULA SRISAI 9,075 Reputation points Microsoft External Staff Moderator

2026-03-03T22:03:27.8733333+00:00
Hello Jackie ,

Thanks for the detailed explanation — since this is occurring across multiple vendors and only during the re‑authentication (e‑signature) prompt, this strongly points to an Entra ID authentication flow issue rather than an app‑specific problem.

What we’re seeing in similar cases is that the re‑auth flow (often using a popup or embedded window) fails after password submission due to browser cookie handling or redirect/token validation during the post‑authentication handoff. Recent browser and Entra ID changes around SameSite cookies, iframe/popup authentication, and redirect handling can result in a blank screen with no explicit error.

Things to check next:

Confirm whether the signature prompt uses an embedded window / iframe / popup rather than a full redirect.

Ask vendors to validate their app supports modern browser cookie requirements (SameSite=None; Secure) for Entra ID re‑auth flows.

Review Entra ID sign‑in logs for a failing attempt — even if the UI shows blank, the logs often reveal token or redirect failures.

Temporarily test disabling Conditional Access sign‑in frequency or re‑auth‑related policies to rule out policy interaction.

Capture browser DevTools network/console logs at the moment the screen goes blank (this is especially useful for vendors).

Since multiple platforms are affected, Please share the details in private message.
Nik Hunt 0 Reputation points

2026-03-04T10:37:45.7033333+00:00

Just to add we are also experiencing this issue - have seen it happen in the last few days. Usually hitting F5 reloads the authentication window and the logon completes.

1 answer

Your answer

VEMULA SRISAI 9,075 Reputation points Microsoft External Staff Moderator

2026-03-03T22:03:27.8733333+00:00

Hello Jackie ,

Thanks for the detailed explanation — since this is occurring across multiple vendors and only during the re‑authentication (e‑signature) prompt, this strongly points to an Entra ID authentication flow issue rather than an app‑specific problem.

What we’re seeing in similar cases is that the re‑auth flow (often using a popup or embedded window) fails after password submission due to browser cookie handling or redirect/token validation during the post‑authentication handoff. Recent browser and Entra ID changes around SameSite cookies, iframe/popup authentication, and redirect handling can result in a blank screen with no explicit error.

Things to check next:

Confirm whether the signature prompt uses an embedded window / iframe / popup rather than a full redirect.

Ask vendors to validate their app supports modern browser cookie requirements (SameSite=None; Secure) for Entra ID re‑auth flows.

Review Entra ID sign‑in logs for a failing attempt — even if the UI shows blank, the logs often reveal token or redirect failures.

Temporarily test disabling Conditional Access sign‑in frequency or re‑auth‑related policies to rule out policy interaction.

Capture browser DevTools network/console logs at the moment the screen goes blank (this is especially useful for vendors).

Since multiple platforms are affected, Please share the details in private message.
Nik Hunt 0 Reputation points

2026-03-04T10:37:45.7033333+00:00

Just to add we are also experiencing this issue - have seen it happen in the last few days. Usually hitting F5 reloads the authentication window and the logon completes.

Answer 1

Hello Jackie,

Welcome to the Microsoft Q&A and thank you for posting your questions here.

I understand that your Azure SSO is providing blank screen for multiple platforms.

This is not an application bug, but a modern authentication flow conflict between Azure SSO > App redirect > Browser enforcement of security (SameSite, Secure cookies, embedded context blocking). You should validate this under Microsoft Entra ID > App registrations > Authentication and confirm every reply URL used by the application is explicitly listed, as documented here: Configure authentication in Entra ID – https://learn.microsoft.com/en-us/entra/identity-platform/quickstart-register-app Redirect URI restrictions – https://learn.microsoft.com/en-us/entra/identity-platform/reply-url

Secondly, another frequent root cause involves Conditional Access policies enforcing sign-in frequency or session controls during secondary authentication prompts. When a re-authentication occurs inside a popup or embedded window, certain policies can interrupt token issuance without surfacing a visible error, resulting in a blank page. Microsoft recommends reviewing sign-in logs and evaluating Conditional Access impact through the policy insights and reporting workbook. Temporarily excluding the affected application from strict session policies can confirm whether Conditional Access is interfering with the flow. Official guidance for reviewing these settings is available here: Conditional Access overview – https://learn.microsoft.com/en-us/entra/identity/conditional-access/overview Sign-in logs in Entra ID – https://learn.microsoft.com/en-us/entra/identity/monitoring-health/concept-sign-ins

Thirdly, modern browser security enforcement is another validated cause, particularly regarding SameSite cookie handling. Microsoft identity platform requires cookies used in cross-site authentication flows to be set with SameSite=None; Secure, otherwise browsers such as Edge and Chrome may block them in iframe or popup contexts, leading to incomplete redirects. Applications that embed authentication within iframes are especially susceptible to this behavior. Vendors must ensure compliance with current browser standards and Microsoft’s identity platform requirements, as outlined in the official documentation: SameSite cookie guidance – https://learn.microsoft.com/en-us/entra/identity-platform/howto-handle-samesite-cookie-changes-chrome-browser Authentication flow fundamentals – https://learn.microsoft.com/en-us/entra/identity-platform/v2-oauth2-auth-code-flow

Also, to further isolate the problem, it is essential to capture browser network traces using developer tools during the failing re-authentication attempt. Look specifically for failed authorization code exchanges, HTTP 400/401 responses, redirect_uri_mismatch, or blocked third-party cookies. Microsoft recommends validating that the authorization response successfully returns an authorization code and that the token endpoint call completes without interruption. If copying the blank page URL into a new browser tab completes successfully, this strongly indicates an embedded context or third-party cookie restriction rather than a core identity failure. Troubleshooting guidance for OAuth authorization code flow is detailed here: OAuth 2.0 authorization code flow – https://learn.microsoft.com/en-us/entra/identity-platform/v2-oauth2-auth-code-flow Troubleshoot sign-in issues – https://learn.microsoft.com/en-us/entra/identity-platform/troubleshoot-authentication

I hope this is helpful! Do not hesitate to let me know if you have any other questions or clarifications.

Please don't forget to close up the thread here by upvoting and accept it as an answer if it is helpful.

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Azure SSO is providing blank screen for multiple platforms

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