While Patch Tuesday updates are generally released to deliver the latest security updates to Windows, sometimes they can cause issues as well. Microsoft says that the latest December Patch Tuesday (KB5021233) update for Windows 10 22H2, 21H2, and 21H1, is producing a Blue Screen of Death (or BSOD) with the error code "0xc000021a" on some systems due to a mismatch between HIDPARSE system files (hidparse.sys) in two different system directories. On its health dashboard, Microsoft explains:
Technical note: After installing KB5021233, there might be a mismatch between the file versions of hidparse.sys in c:/windows/system32 and c:/windows/system32/drivers (assuming Windows is installed to your C: drive), which might cause signature validation to fail when cleanup occurs.
To mitigate the issue, Microsoft has provided detailed steps:
Workaround: To mitigate this issue on devices already experiencing it, you will need to use Windows Recovery Environment (WinRE) with the following steps:
- You will need to enter Windows Recovery Environment. If your device has not automatically started up into WinRE, please see Entry points into WinRE.
- Select the Troubleshoot button.
- Select the "Start recovery, troubleshooting, and diagnostic tools" button.
- Select the "Advanced Options" button.
- Select the "Command Prompt" button and wait for your device to restart, if needed.
- Your device should restart to a Command Prompt window. You might need to sign into your device with your password before getting to the Command Prompt window.
- Run the following command (Important: If Windows is not installed to C:\windows you will need to modify the command to your environment): xcopy C:\windows\system32\drivers\hidparse.sys C:\windows\\system32\hidparse.sys
- Once the previous command completes, type: exit
- Select the "Continue" button.
- Windows should now start up as expected.
Important: It is not recommended to follow any other workaround than those recommended above. We do not recommend deleting the hidparse.sys from your Windows\System32 folder.
Aside from this, there are also several other issues on Windows 10 as well as Windows 11 that you can read about here.