How to fix the blue screen error code “0xC00021A” in Windows 10 and 8

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Marie-Ange Demory
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In case you get the error “0xC00021A”, we recommend that you read this guide where you will learn how to fix the blue screen error code “0xC00021A” in Windows 10 and 8. On the other hand, we have several guides for this type of problem, such as the error of “checking the data of the Dmi pool” and many others.

What is the error "0xC00021A"

On many occasions the error "0xC00021A" when Winlogon.exe and Csrss.exe system files fail. The above are very important files for the proper functioning of Windows, so their failure means that the computer cannot continue to be used.


The Winlogon.exe file performs very important tasks for Windows, in fact, if there are multiple users on the computer and changes are made, the software intervenes directly. In fact, Winlogon.exe is responsible for the upload files for each of the profiles of our system, as well as other relevant activities


The Csrss.exe file appeared in Windows from its earliest versions, today it is said that the file controls it aspects of the Windows console and the shutdown process. Certainly its functions are very important for the correct functioning of the system.

Causes of error '0xC00021A'

One of the main causes of this annoying inconvenience is the appearance of malicious programs. Viruses are often created specifically to target the Winlogon.exe and Csrss.exe executables, which, as we have said before, are essential for the proper functioning of the computer.

In short, the most likely cause for the appearance of the “0xC00021A” error is the presence of a virus. In any case, there could be other causes, in fact a blackout is also capable of corrupting some files on the hard drive, as in the case of those mentioned above.

There are several reasons why this error is displayed, but regardless of which one affects you, we will point out some possible solutions for this problem. But first, it is recommended to clean and speed up your PC with Advanced SystemCare.

How to fix the blue screen error "0xC00021A" in Windows 10 and 8

Here are some of the solutions easier to correct the error "0xC00021A". Read carefully to find the solution and prevent this annoying blue screen from appearing.

Boot into Safe Mode

Realizing that this problem usually prevents access to the system, you will need to boot into safe mode. The process for booting in this mode is simple, just turn off the computer directly from the button on the cabinet. Repeat this process several times.

After doing the above, the Windows Start Menu should appear, which you will recognize as a typical blue background screen. Here you should select “Troubleshoot” and then go to the option "Startup Settings". Next, click on the “Restart” button.

After the above, the system will boot in Safe Mode, here we recommend that you uninstall any suspicious software which you think may have caused the problem.

Turn on automatic repair

For this you will need to create a bootable USB drive with Windows, after doing this process, boot directly from the USB. In other words, this process will be similar to installing Windows from scratch, only this time we're trying to fix the computer.

Wait until the installer starts, then all you need to do is go to “Repair your computer”. In this section, go to "Advanced Options" and locate the option "Automatic repair". After this process, Windows will analyze each of the files that make up the operating system and try to repair any that may be damaged.

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