How To Repair: BSOD Error 0xC000021A

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Restart your computer.
Press the F8 key or the F11 key.
When prompted, select a layout and keyboard.
Click Troubleshoot.
Click on more options.
Click System Restore.
Select an operating system.
The system will now be restored. Click “Next.

Similarly, this stop code 0xc000021a is also an error in the Windows 10 operating system. This is a blue screen error that occurs when your system freezes after updating or reinstalling the operating system. This Windows 10 stop code 0xc000021a says “Your PC has encountered a problem and needs to restart.

STATUS_IMAGE_CHECKSUM_MISMATCH check failed with value 0xC0000221. This indicates that the system driver or DLL has been corrupted. This theme is for programmers. If you are a customer who received a blue screen error code while using a computer, see Troubleshoot blue screen errors.


The error check STATUS_SYSTEM_PROCESS_TERMINATED has the value 0xC000021A. This means that an error has occurred in a large user mode subsystem.


This error occurs when a user-mode subsystem such as WinLogon or the CSRSS (Client Server Run-Time Subsystem) has been fatally compromised and security can no longer be guaranteed. The operating system then switches to kernel mode. Microsoft Windows cannot run without WinLogon or CSRSS. This is one of the few cases where a service failure in user mode can cause the system to shut down.

Incorrect system files can also lead to this error. This can happen if you have recovered your hard disk from a backup. Some backup programs may skip restoring system files they consider to be in use.

0xC000021A error usually appears on a Microsoft Windows 10 machine after upgrading from a previous version of Microsoft Windows or after performing a repair installation. When you get the blue screen of death, the one below will appear on your screen.

Now, before we panic, let’s look at some ways to correct this error.

Repair corrupted files

I still want to start fixing corrupted files on your system because I’ve solved a lot of systems that don’t boot in my time. I also like to do it first, because it means we’re not making any changes to the system. To repair corrupted files, proceed as follows.

– Insert your Windows 10 DVD into your system and start the DVD. (If your system does not have a DVD drive, you can download a Windows 10 ISO from the Microsoft website and create a USB boot drive.

On the first screen, click on “Troubleshooting”.
Then click on “Advanced Options”.
Then click on “Prompt”.

A black window should appear, in the chkdsk window type C : /f /r, this will launch a chkdsk on your system that will correct /f = disk error, and /r will find and recover the bad sectors. When you receive a y/n prompt, type y and press Enter. Now restart your computer and hope it starts correctly.

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Using sfc /scannow or DISM


To fix this bug, we need to use our old sfc /scannow or DISM friends. If you cannot boot on the desktop to access the CMD, use the installation media to boot in safe mode and select “Safe mode with command prompt” in the options.

1. open a CMD window as administrator.

2. Enter or paste ‘sfc /scannow’ and press Enter.

3. Have the procedure and necessary repairs carried out.

If the error persists, try DISM.

1. open a CMD window as administrator.

2. Enter ‘dism/online/cleanup-image/restorehealth’ and press Enter.

3. Have the procedure and necessary repairs carried out.–status-system-process-terminated

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