All of a sudden my Windows Hello camera stopped working. (When I wanted to login to Windows 11 it said ”preparing…”, and then a failure message after a few seconds – and the PIN-fallback login kicked in).
I had an entry in the Windows logs (Program section) stating a problem in the BioEnrollmentHost.exe (version 10.0.22000.120) in the module twinapi.appcore.dll (version 10.0.22000.469).
Solution
Looking in the Device Manager of Windows 11 (the old one, which you get to from Right clicking start button, and then selecting ”Device Manager”).
Inoticed that I had an entry with a yellow warning triangle added to its icon. The entry was for Microsoft Streaming Service Proxy.
As soon as I uninstalled this device driver, Windows Hello started working again!