Microsoft is investigating a known issue that leads to Blue Screen of Death (BSOD) errors with code 0xc000021a after installing Windows 10 cumulative update KB5021233 that was released last Tuesday (Patch Tuesday).
The company warned over the weekend that "after installing KB5021233, some Windows devices may start with the error (0xc000021a) on a blue screen."
This problem is likely caused by a mismatch between the versions of the hidparse.sys files in system32 and system32/drivers in the Windows folder, "which can cause signature validation to fail when cleanup is performed."
The list of affected platforms ranges from Windows 10 20H2 to the latest version, Windows 10 22H2.
Redmond added that it is already working on a fix to address this issue, but has yet to say when it will be ready.
However, the company shared a temporary solution to resolve the blue screen issue.
This requires users to copy the hidparse.sys file from the system32\drivers folder to system32 via the Windows Recovery Environment (WinRE) so that signature validation no longer fails during cleanup.
To fix the problem on the affected devices, you should follow the steps below:
You will need to enter the Windows Recovery Environment. If your device is not automatically booted into WinRE, 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 reboot if necessary.
Your device should reboot into a command prompt window. You may need to sign in to your device with your password before going to the command prompt window.
Run the following command (Important: If Windows is not installed in C:\windows, you will need to modify the command for your environment):
xcopy C:\windows\system32\drivers\hidparse.sys C:\windows\system32\hidparse.sys
Once the command is complete, type: exit
Select the “Continue” button.
Windows should start without a problem.
“It is not recommended to follow any solution other than the one suggested above. We do not recommend deleting hidparse.sys from the Windows\System32 folder,” Microsoft says.