Single User when logging into Windows getting 401 Error on ALL Internal Websites, External are fine

Question

Single User when logging into Windows getting 401 Error on ALL Internal Websites, External are fine.

Edge Browser shows user Icon Picture, upper left corner and shows her logged in correctly.
Did an Edge Trace and found that ALL Internal sites are connecting using Port 80, not 443. Even if user enters HTTPS for a site that uses Port 443, it loads it as Port 80 and fails to load it.

Workaround for most of users work, not all... was to have her Log out of the logged in Profile in the Browser. Close Browser and try again. It then loads her "Logged in Profile" correctly, apparently. since she can now load internal websites. But, next time she logs into Windows, even on a NEW PC, it still loads the Browser (two Tabs), both are internal sites, but shows 401 error again.

To even do her job, she always has to log out of the Browser Session and start a new one.

Answer 1

Hello

Thank you for posting in Q&A forum.

The 401 error typically indicates an authentication problem, and the fact that internal sites are connecting using Port 80 instead of 443 suggests a potential misconfiguration. Here are a few steps you can try:

1. Ensure that the internal sites are added to the "Trusted Sites" list in the browser settings. Go to Settings > Privacy, search, and services > Security and make sure "Use secure DNS to specify how to look up the network address for websites" is enabled.
2. Disable Loopback Check:

Open PowerShell as an administrator and run the following command to disable the loopback check:

New-ItemProperty -Path "HKLM:\System\CurrentControlSet\Control\Lsa" -Name "DisableLoopbackCheck" -Value 1 -PropertyType dword

3. Clear the browser cache and cookies and then restart the browser.
4. Ensure that the internal sites are configured to use the correct authentication method. Sometimes, switching between different authentication methods (e.g., NTLM, Kerberos) can help resolve the issue.
5. If the issue persists, check the Group Policy settings related to browser and network configurations. There might be policies enforcing the use of Port 80.

I hope the information above is helpful.

If you have any questions or concerns, please feel free to let us know.

Best Regards,

Daisy Zhou

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