topic Qlik Replicate Console UI 401 Error After Windows Client Upgrade in Qlik Replicate

Qlik Replicate Console UI 401 Error After Windows Client Upgrade

EE_ — Mon, 24 Nov 2025 08:56:47 GMT

Our Qlik Replicate is installed on a Windows Server. After performing a Windows upgrade from Windows 10 to Windows 11 on an external computer, we suddenly could no longer access the Replicate UI.

The error indicated a missing certificate, so we installed the CA certificate. On the Windows Server, the connection now shows as a valid secure connection. However, when connecting to the Qlik Replicate Console UI from the external computer, we receive a 401 Unauthorized error.

We would like to understand:

What are the possible reasons why the Qlik Replicate Console UI returns a 401 Unauthorized error from external machines after updating the certificate?
What server or framework does the Qlik Replicate UI use? Is it based on IIS, Tomcat, or Apache?
We need to understand the underlying architecture to determine why updating the certificate affects external UI access.

Re: Qlik Replicate Console UI 401 Error After Windows Client Upgrade

john_wang — Mon, 24 Nov 2025 09:27:19 GMT

Hello @EE_ ,

If I’m reading the situation correctly, Replicate is running on a Windows Server, and you’re accessing its GUI from a Windows client machine that was recently upgraded from Windows 10 to 11. After the upgrade, the browser stopped working with the console. A few things to check:

Cached browser data might be the culprit.
Try a different browser such as Chrome, Edge, or Firefox, or open Chrome in Incognito mode to rule out cache issues.
Replicate’s web console isn’t tied to IIS, Tomcat, or Apache.
It uses its own built-in web server, so the issue isn’t related to those components.
Confirm whether loopback was disabled.
If it was, you’ll need to reboot the Windows Server for the change to take effect.
https://community.qlik.com/t5/Official-Support-Articles/How-to-change-the-Qlik-Replicate-URL-on-a-Windows-host/ta-p/2042112

Hope this helps.

John.

Re: Qlik Replicate Console UI 401 Error After Windows Client Upgrade

EE_ — Fri, 28 Nov 2025 05:49:02 GMT

Hello @john_wang ,

We have confirmed that the loopback check has been disabled and the Windows Server has already been rebooted afterward.
We also tested using different browsers and Incognito/Private mode, but the same error still appears.

Please refer to the attached screenshots.

chrome

edge

May I ask what additional areas we can investigate to further troubleshoot this issue?
Thank you

Re: Qlik Replicate Console UI 401 Error After Windows Client Upgrade

john_wang — Sat, 29 Nov 2025 03:28:43 GMT

Hello @EE_ ,

It looks like this may be a network-related issue. On the Windows client, try running a simple ping test to the Windows server’s hostname or IP address to check for connectivity problems.

Also review the firewall settings on the Windows server. For troubleshooting, you can temporarily disable the firewall to verify whether it’s blocking the connection. If it turns out to be the culprit, add the required ports or the application itself to the allowlist.

Regards,

John.