Microsoft has admitted that the KB5021233 update released during this month’s Patch Tuesday event day has caused a 0xc000021a blue screen error on some Win10 devices after the update. After installing KB5021233, some Windows devices may experience a blue screen error (0xc000021a) at startup,” Microsoft wrote in the official changelog.
Microsoft says this known issue is caused by a file version mismatch between hidparse.sys in system32 and system32/drivers in the Windows folder, causing signature verification to fail. Currently, feature updates from Win10 20H2 to Win10 22H2 are affected. Microsoft says it’s working on a fix.
Microsoft also shared a temporary fix:
- Enter Windows Recovery Environment mode
- Select the “Troubleshooting” option
- Select “Start recovery, troubleshooting, and diagnostic tools”
- Select “Advanced Options”
- Select the “Command Prompt” button, you may need to wait for your device to restart if necessary
- Your device will reboot into a command prompt window and log in with your password
- Run the following command:
xcopy C:\windows\system32\drivers\hidparse.sys C:\windows\system32\hidparse.sys
- After the command completes, type “exit”
- Select the “Continue” button
- It should be normal after restarting.
Microsoft added: “In addition to the methods recommended above, no other solutions are recommended. We do not recommend deleting hidparse.sys from your Windows\System32 folder.”