Windows Store/UWP apps hang in background (no GUI), Wi-Fi forgets profiles, and search indexing broken after KB5120998 update attempt

Question

Hello,

After Windows Update attempted to install the latest cumulative update (KB5120998 on Windows 11 24H2/25H2 build 26100), several core system services and the UWP app subsystem completely broke:

1. UWP / Store Apps Broken: Applications packaged through the Microsoft Store (such as WhatsApp, Minecraft Launcher, Lenovo Vantage, and even Feedback Hub) create background processes visible in Task Manager, but no graphical window/UI ever renders.
2. Network / Wi-Fi Credential Loss: Every time the system restarts, Windows forgets all saved Wi-Fi networks and passwords. Re-entering credentials often triggers connection errors.
3. Search Indexing Error:__ Windows constantly displays notifications stating that search indexing is turned off/disabled
4. Checked CBS.log, which showed RebootPending locks and driver staging interruptions (UpdateAgentLCU) during preshutdown..

The processes remain stuck in memory without crashing or throwing explicit error codes. How can the damaged AppContainer/DPAPI credential vault subsystem be repaired without performing a clean installation?

Answer 1

Thank you for updating me with that information.

Please try to return to the login screen

While holding the Left Shift key, click the Power icon at the bottom right > Restart

This will bring you to Windows Recovery Environment

Select Troubleshoot > Advanced Options > Uninstall Updates

Uninstall latest quality update

If this doesn't work, Select Troubleshoot > Advanced Options > System Restore

Choose the restore point at an earlier date where everything is still working

Click Next then Finish

Answer 2

Hi, good day!

Microsoft has begun implementing and releasing Optional preview updates that are typically released on the 3rd or 4th week of every month. These updates allow admins to test the patch before its mandatory launch on Patch Tuesday (2nd week of the month). If you are not experiencing any issues with your system, there is no need to install the KB5120998 preview update.

I recommend reporting the issue via Feedback Hub app to notify Microsoft.

https://support.microsoft.com/windows/send-feedback-to-microsoft-with-the-feedback-hub-app-f59187f8-8739-22d6-ba93-f66612949332

Please try to uninstall the recent KB5120998 preview update.

https://support.microsoft.com/windows/how-to-uninstall-a-windows-update-c77b8f9b-e4dc-4e9f-a803-fdec12e59fb0

If this fixes the issue, please try to temporarily pause updates to prevent it from reinstalling.

Open Settings > Windows Update > Pause updates > Pause for 1 week

To prevent optional preview updates from appearing and installing in the future, press Start > Settings > Windows Update. Toggle off "Get the latest updates as soon as they're available" option. Restart your computer.