Windows 10 updates come out almost every now and then and the latest update KB5021233 just launched last Tuesday, Microsoft confirmed that for some Windows 10 devices, after the update it may appear a blue screen crash and display error message 0xc000021a, the cause is currently under investigation, which means friends who have not yet upgraded, please remember to wait a bit. If you upgrade and encounter this problem, there is also a temporary solution and I will fix it for everyone below .
Slow Down Before Updating!Microsoft Confirms Latest Windows 10 KB5021233 Causes Blue Crash Screen on Some Devices
Since the release of Windows 10 update KB5021233 last Tuesday, on foreign Microsoft forums and Reddit websites, users have reported blue crash screens and 0xc000021a error messages, like this Christopher Dut Quoted: “After the 21H2 auto-update, a blue screen appeared on the first reboot, it reappeared after the reboot. Using the auto-repair feature didn’t fix the problem.” He then tried many methods, but none of they worked:
another tylo leonidas In addition, I have encountered it for 3 consecutive days and cannot figure out the reason after a lot of troubleshooting, and it appears every time it leaves the computer. It can be seen that the blue screen error is erratic and very annoying, especially for those who often need to leave the computer for output, half the output will make people want to destroy the computer:
to exist Reddit forumsIn the post from Microsoft announcing the new version update, many users reported that they encountered the error message 0xc000021a: 
For this reason, Microsoft confirmed this problem on the official website, it may be caused by the file version mismatch between hidparse.sys in system32 and system32/drivers in the Windows folder, which may lead to signature verification error during cleaning:
Microsoft also provides a temporary solution, but you need to go to Windows Repair Environment (Windows RE) and copy hidparse.sys file from system32drivers folder to system32 to avoid signature verification errors during cleanup (Click me to read the instructions）：
- You will need to enter the Windows repair environment. If your device did not automatically boot into WinRE,Watch the tutorial on how to get into WinRE。
- Select the Troubleshoot button.
- Select the Launch Recovery, Troubleshooting and Diagnostic Tools button.
- Select the Advanced Options button.
- Select the Command Prompt button and wait for the device to restart (if necessary).
- Your device should reboot into a command prompt window. You may need to log in to your device with a password before you can access the command prompt window.
- Run the following command (important: if Windows is not installed in C:windows, you need to modify the command according to your environment): xcopy C:windowssystem32drivershidparse.sys C:windowssystem32 hidparse.sys
When the above command completes, type: exit - Select the Continue button.
- Windows should now boot as expected.
Microsoft also added that it does not recommend following any other workarounds than the ones suggested above. It is not recommended to delete hidparse.sys from WindowsSystem32 folder.
