Microsoft recently released monthly update KB5008215 to Windows 11 running PCs. The update brings many security improvements for windows components.

But the update is failing to install, causing performance issues for many users. Users also complained about facing startup issues and high CPU spikes because of very aggressive Antimalware Service Executable. These issues have been reported at Reddit and official Microsoft forum by users.

Fails to install:

Users have reported 1, 2 that the update KB5008215 fails to install with error code 0x80073712.

2021-12 Cumulative Update for Windows 11 for x64-based Systems (KB5008215) FAILS to install.
I cannot even install this update and it fails to install every time I attempt downloading this update. I get this error message every time I try to update, “Some update files are missing or have problems. We’ll try to download the update again later. Error code: (0x80073712).

I have tried everything to resolve it and nothing has worked. I have run SFC, DISM, DSCK, tried to repair my system files, run the windows update trouble shooter and the problem continues to persist.

Performance issue:

Many users have reported facing performance degradation issues after installing the update KB5003637. This is what one of the users has reported at the official Microsoft forum.

CPU stuck at 0.5 GHz after tueday patch KB5008215

I encountered a weird bug with the last Tuesday patch.

I couldn’t log in after the first reboot.

My mouse was stuttering and I was unable to type my password or anything…

Second reboot seemed fine but after a while I noticed my Ryzen 9 3900X was struggling doing some basic stuff like web browsing, reading emails…

I opened task manager and saw the CPU frequency was stuck at 0,5 GHz (screenshot).

I think it was working fine for a few hours and then locked itself at 0,5GHz.

Users have also complained about facing NVMe SSD related issues. You can read the user complaints by clicking here.

Nope I’ve had the November update and now this new update and it’s not fixed in either. The December one is a security update anyway so would not expect any SSD write fixes in that. My write speed in CrystalDiskMark (using the NVMe SSD mode) is still 2800-3200MB/s between multiple runs on a 970 Evo Plus which has a spec write speed of 3300MB/s.

So whilst I can get the max spec write speeds, it’s up and down through multiple runs.

Startup and other issues:

Some users have reported about facing many startup issues after installing the update.

After installing this update, numerous issues arose, which even uninstalling the update did not resolve. OneDrive, Google Drive, Amazon Photos and Box Cloud would not start up with Windows. Not only wouldn’t any of these services start up with Windows, the option, the app itself and the off/on toggle switch had disappeared from settings-apps-startup. Ultimately I discovered that by starting each of these services manually – with the exception of Box – I was able to get the startup with Windows function restored. After the manual restart, I got a fly-out messages that said, “Now configured to run when you log in” and by some miracle the app and toggle switch were restored to settings-apps-startup. To get Box working, I had to uninstall the app and reinstall it; trying to start it manually didn’t work.

One of the user has reported a bug causing high CPU spikes because of very aggressive Antimalware Service Executable Process.

There is some bug in this latest build. The Antimalware Service Executable Process is very agressive in Task Manager with high CPU spikes and attach itself to certain application when open. I have to close every applications to find out what application is causing the Antimalware Service Executable to spike and only when it closed down the Antimalware Service Executable stop running at 10-20% CPU.