Qlik Sense February 2024: Error creating a new data connection or adding data from an existing data connection

[Sebastien_A]

Creating a new data connection or adding data from an existing data connection may fail in Qlik Sense February 2024. 

The following errors can be observed:

404
The following resource cannot be found.
The URL is unknown.

or

400
Bad Request
The http header is incorrect.

The issue occurs when a custom virtual proxy prefix is in use.

Resolution

Upgrade to resolve QB-25165. 

Workaround:

No workaround is available.

Fix Version:

Qlik Sense Enterprise on Windows February 2024 Patch 3. See Release Notes.

Cause

Product Defect ID: QB-25165

Environment

Qlik Sense Enterprise on Windows February 2024 IR to Patch 2

[Lauri]

Applying patch 3 to Feb 2024 a week ago resolved this issue for me. But today I uninstalled patch 3 in preparation for the Postgres upgrade, I upgraded/unbundled Postgres from 12.5 to 14.8, and then I applied patch 3 again and rebooted. Everything is working in Qlik but I'm getting the 400 error again. Any further steps I can take?

[Lauri]

Strange thing: After about 20 minutes, 400 error stopped appearing.