KB5021233 – Causing Blue Screens


Are you having recurrent issues with blue screens on your Windows 10 computer? You might be dealing with the KB5021233 update.

This latest security update has been causing a lot of problems for many users, resulting in frequent blue screen errors.

If this is something you’re experiencing, then read on to find out what could be causing it and how to fix it.

This was our situation with the client – I’m sure you can relate!

After the initial computer restart, a dreaded Blue Screen of Death appeared. Following another reboot, that same error was still present even after an automatic repair attempt failed to fix it. A system restore and attempts using Windows System File Checker (SFC) as well as chkdsk all had unsuccessful outcomes too – so we tried ‘DISM’ to reverse any actions taken previously but sadly with no luck either!

At the next restart, we got: Automated repair SrtTrail.txt: “A recently serviced boot binary is corrupt.

Then we got our tech gloves on! 🙂


KB5021233 is a security update that features some major changes to Windows 10. Cortana is being removed from the taskbar – no more talking to your computer! It’s all part of Microsoft transitioning away from its current OS as they move into developing Windows 11.

If you are a Windows 10 user, you may be getting a blue screen (which just happened to one of our clients this morning!) due to a glitch with Microsoft’s recent KB5021233 cumulative update. The bug triggers the dreaded “Blue Screen of Death” and an 0xc000021a error, causing much anguish for those affected!

If you’re running a Windows 10 client version from 20H2 to the latest 22H2, watch out for an issue caused by versions of hidparse.sys in system32 and system 32/drivers folders that don’t match up!

This looks like the cause of the bluescreen.

Workaround / Fix


Run Chkdisk

The first step in running chkdsk outside of Windows 10 is to download a third-party “bootable media” such as Kaspersky Rescue CD or Windows Boot Media.

These allow you to create an environment where CHKDSK can be executed without having to boot into Windows 10.

Once you’ve got the bootable media prepped, all that’s left to do is configure your computer so it boots from there instead of its internal hard drive. 

After that, run chkdsk with the following commands: 

chkdsk /f /r /x 

/f – this flag checks for any errors on the disk and attempts to fix them if found 

/r – this flag scans for any bad sectors and attempts to recover readable information from them if found 

/x – this flag forces the volume dismounting before checking begins 

Run sfc/scannow command

Create a bootable USB drive with the Windows 10 installation media on another computer or laptop.

Then, plug your USB drive into your computer and boot up from it instead of your regular operating system. Once inside the Setup screen, select Repair Your Computer > Advanced Tools > Command Prompt > sfc /scannow.

This will start the System File Checker process as before, checking all system files and replacing any corrupted or missing ones with good copies from a cached folder 

Replace the old hidparse.sys file  

We tried to attempt a fix using the WinRE environment – If the signature validation keeps failing during cleanup, your computer’s WinRE will need to be employed to successfully place a copy of hidparse.sys into system32 from its original home in the driver’s folder of system32!

  1. Don’t worry – getting into Windows Recovery Environment is easy! Just boot up your device and if it doesn’t do so automatically, just select WinRE during the startup
  2. Click on “Troubleshoot”
  3. Click on “Start recovery, troubleshooting, and diagnostic tools”
  4. Selection the option that says “Advanced Options”
  5. Choose “Command Prompt” and wait for your machine to boot up.
  6. When your computer starts, you will be prompted to enter the Command Prompt mode.
  7. Just run the following command : xcopy C:\windows\system32\drivers\hidparse.sys C:\windows\system32\hidparse.sys
  8. Click on ‘Continue’ in the next screen.
  9. This should hopefully get you back in Windows


Hopefully, the above steps should get you back into your Windows! If you are stil having issues, our PC repair geeks will get you up and running in no time!

Technology is great as long as it works! Updates are welcome as long as nothing breaks!

KB5021233 is a great security update that improves and updates several components. We hope Microsoft irons out all its issues so that we as users can have a better experience!

I am a computer engineer holding a bachelor's degree in Computer Science, complemented by a Master's in Business Administration from University of Strathclyde, Scotland. I currently work as a Senior IT Consultant in Melbourne, Australia. With over 15 years of...