Edge and Chrome issue with sharepoint auth

It seems that the issue you are experiencing with SharePoint authentication in Edge and Chrome may be related to the recent update of Edge. Since the problem started after the browser update and is affecting multiple users, it could be a compatibility issue with the updated version of Edge, especially since you mentioned that Firefox is working without issues.

Here are a few troubleshooting steps you can consider:

1. Check TLS Settings: Ensure that your organization is compliant with the TLS 1.2+ requirement. If users are on older versions of Windows (like Windows 7 or 8), they may face authentication issues due to TLS deprecation.
2. Browser Privacy Mode: Since you mentioned that InPrivate mode and clearing cache did not help, it might be worth checking if the issue persists in a completely fresh profile or after resetting browser settings to default.
3. Group Policies: Review any Intune policies that might affect browser behavior, even if no changes were made recently. Sometimes, policies can have delayed effects or interactions.
4. Contact Microsoft Support: Since Microsoft Support is already looking into the SharePoint and M365 services, keep them updated with your findings, especially the correlation with the Edge update.
5. Monitor for Updates: Keep an eye on any new updates for Edge or Chrome that might address this issue. Sometimes, subsequent updates can resolve newly introduced bugs.

If the issue continues, you may want to consider temporarily using Firefox as a workaround until a permanent solution is found.

References:

• Authentication errors when connecting to SharePoint or OneDrive from Windows 7 or 8

Hi Imrinder, I’ve looked into this and it seems the issue is tied to the latest Edge update, which uses the same Chromium engine as Chrome. The update likely changed how cookies and authentication tokens are handled, and that’s causing SharePoint sign-in to fail while other M365 apps still work. Firefox works because it doesn’t use Chromium. Let’s start with a quick check: in Edge or Chrome, go to settings and make sure third-party cookies aren’t blocked, or add exceptions for *.sharepoint.com and login.microsoftonline.com. Also, check if Enhanced Security Mode is enabled in Edge and turn it off temporarily to test. If you’re managing these browsers through Intune, can you confirm if any policies like “Block third-party cookies” or “Clear cookies on exit” are applied? Lastly, have you noticed if this happens only on devices with Conditional Access or MFA? Let me know what you find .

Thanks for confirming those steps. Since cookies, security mode, and Intune policies are ruled out, and MFA changes didn’t help, this strongly points to a Chromium-based browser bug introduced in the latest Edge build. It’s likely affecting how authentication tokens for SharePoint are handled, which explains why Firefox works and why even a clean Windows install didn’t fix it. At this point, the best next step is to check if the issue persists in Edge Beta or Dev channels, or temporarily roll back to a previous stable version to confirm it’s version-specific. Can you test with Edge Beta or an older build? Also, do you notice if this happens only on devices with the latest Windows updates, or across all OS builds? If it’s consistent, we may need to escalate as a browser regression and apply a temporary workaround like deploying Firefox or using the OneDrive client until Microsoft releases a patch.

That new detail is really helpful. If InPrivate works for any account on the same device, but normal mode fails for the user on their own device, it points to something tied to the local profile or the way the browser is handling cached credentials and the Windows Account Manager (SSO broker). The update may have broken how Edge/Chrome interact with Web Account Manager for single sign-on.

Here’s what I’d suggest next: • Check if Web Account Manager (WAM) integration is enabled in Edge. Go to edge://settings/profiles and confirm “Sign in automatically” is on. • Try disabling SSO via WAM temporarily by setting the policy BrowserSignin to 0 and see if login works manually. • Clear Windows Credential Manager entries for login.microsoftonline.com and sharepoint.com on the affected device. • If you have Workplace Join or Azure AD registration, confirm the device is still showing as compliant in Azure AD.

Can you check if the affected devices are Azure AD joined or hybrid joined? And do they have multiple accounts signed into Edge? This will help confirm if the issue is WAM/SSO related.

This looks to me a WAM reset or disabling the SSO vuia WAM and even clearing the Credential Manager.