Stop: 0xC000021A is a windows error and is thrown when an essential system process has been tampered or the security aspect of the file has been compromised. It is also misread by many people as “c00002la error” in the blue screen. The System automatically activates the Kernel mode. The two files which are mostly taken into consideration are WinLogon and CSRSS. The worst part is that the windows architecture is unable to run without these two files and hence the system crashes abruptly.

What is stop c000021a fatal system error?

Sometimes it does happen that you have installed an application and it somehow crashed your system. You have decided to restore your old settings and select the old configuration. Now you no longer find the error related to the removed application but instead get this message on your screen. This is a very critical condition and you need to be very careful while trying to troubleshoot it.

Windows Error Message

Following are two error message which are generally displayed in the blue screen fatal system error log:

c000021a fatal system error

stop c000021a fatal system error

Why c000021a error cannot be corrected in GUI mode?

This is a user-mode error and the files associated – CSRSS and WinLogon are the core files which handle the GUI login interface. So without these two files it is impossible to log into the GUI mode and hence there is no chance of GUI troubleshooting mode.

Also most evident 3rd party apps generally trigger this situation and when you remove them they leave behind the marks of infection in this manner. The fatal system error blue screen is not something which pops up every now and then. We all know that Windows efficiency level is a bit low compared to LINUX or Mac but it is the user who is responsible for this error in most cases. One worth mentioning scenario is the Game patch files and software key-gens.

How to repair c000021a error?

The only effective way is to restore the computer settings to its last working condition. It cannot be guaranteed but this trick works most of the time. The steps for restoring the system files are -

1. Restart your system
2. Press F8 on start-up (Keep tapping)
3. Select Advanced Options
4. Select Last Known Good Configuration
5. Wait till your system restarts

Alternative Solutions for c000021a error

1. If you have a FAT partition try using an MS DOS startup disk to get into the System hard drive. Take a back up of the primary partition. Re-install Windows.
2. If are having this problem after installing a new hardware, remove it and then restart your system. If the system starts up normally the new hardware is faulty. Try contacting the hardware manufacturer.
3. Emergency Recovery Disks are of great help under these circumstances. If you were smart enough to make one it is time they can help you get rid of this problem.
4. Try contacting the Microsoft Team if the problem persists.

Unable to repair c000021a

If all tricks fail try contacting the software or the hardware manufacturer for which you are facing the problem. If you have anything to ask about this problem post back in the comment section. We would be more than happy to help.