Here’s how you can fix error 0xc000021a which usually comes in Windows 10 and Win 8. These newer versions of Microsoft Windows operating systems (OS) arrived with a number of issue and problems at the time of launch. After some time, the company pushed updates with time.
Majority of errors were resolved, but a handful of them was left intact. One of those is associated with the hex code 0xc000021a. Further, this code states “Your PC Ran Into A Problem and Needs To Restart.” It comes inside a Blue Screen of Death (BSoD) error. It looks a little different in Windows 7 and states “An error has been detected.”
Fix Error 0xc000021a
- 1 Fix Error 0xc000021a
- 1.1 Reasons / Cause of the Error 0Xc000021A
- 1.2 Solutions to Fix the Error 0Xc000021A
These BSoD errors have the ability to seriously damage the internal structure of Windows OS. It doesn’t usually solve even after restarting the PC. At times, performing a system restore may not work. So, you should know the real cause behind the error message and then, its solutions.
Reasons / Cause of the Error 0Xc000021A
The main cause behind it is the Windows updates. After getting updated, it doesn’t boot to Windows and the error code 0xc000021a comes on the blue screen of death. The reason behind it is the following two files.
- winlogon.exe: This file is associated with the login and logout operations of Windows. Sometimes, it gets damaged due to mismatch of System Files or 3rd party software. When the file damages, error causes the PC to boot to the Windows login.
- csrss.exe: This file belongs to Microsoft server / client. Sometimes, it also gets damaged.
Related: Error Code 0x80070426.
Solutions to Fix the Error 0Xc000021A
Following are the solutions. These will fix the 0xc000021a error.
Solution # 1: Repair Corrupt System Files
Reimage Plus can help in this case. You need to download and run it. Click here to scan for corrupt files. If corrupt and missing files are found, repair them.
Solution # 2: Booting Windows Manually
Try and boot Windows manually. Boot in safe mode using force drivers to have the signature disabled option available in Advanced Boot Options. Follow the listed steps to do it.
- Restart the PC by pressing Shift key + clicking on the Restart button. If you can’t access Restart option, you will need to boot the Windows using a WIndows bootable USB.
- An option screen will open. Click on Troubleshoot to open the advanced tools.
- Then, click on the Advanced option.
- Click on Startup Settings.
- A number of options will appear. Select ‘Press F7 labeled as Disable Driver Signature Enforcement.’
Now, the PC should restart with the selected option. While booting up, a number of different options will appear, you can tweak your PC now.
Solution # 3: Fix the Issue using SFC Scan
If the above method doesn’t work, you can employ System File Check Scan (sfc scannow) to resolve the issues. The scan will fix the corrupted files from the cached copies. Run a full SFC can on your PC.
Method # 4: Reset the computer’s BIOS
Many users fix the issue by resetting the BIOS. It can be done simply by removing the CMOS battery from its motherboard for a couple of minutes. Before opening the computer’s chassis, make sure it’s not connected to electricity by any power cable. However, this trick won’t work with laptops as their motherboards are not readily accessible.
Method # 5: Replace any and all corrupted registry hive files with backups
When a computer starts or reboots, it tries to access the essential registry hive files, but couldn’t because they may have been damaged or corrupted. Try to replace any (and all) corrupted registry hive files with their backups. It should fix the issue.
In case, your computer doesn’t (or won’t) start/boot up, you won’t be able to able to replace them via the File Explorer. The workaround is using a Command Prompt in the Windows Recovery Environment.
To access Windows Recovery Enhancement, you will need a Windows installation USB or disc with the same version of Windows as the once installed on your PC.
Following are the steps which you need to follow:
- Restart the computer after inserting the windows installation disc or USB
- As the computer shows the first screen, get inside its BIOS settings and configure to boot from the installation media instead of its HDD/SSD.
- Save and Exit the BIOS
- If prompted, press any key to boot from the installation media.
- Select your language, time zone, and keyboard layout preferences, then click on Next
- On the Install Now button screen, look for and click on Repair your computer in the bottom left corner of the windows.
It will make you reach the Startup Options screen. Then, you need to perform the following steps.
- Click on Troubleshoot > Advanced Options.
- Click on Command Prompt
- Type ‘c:’ command in cmd and press Enter. If you have installed Windows on a partition other than C drive, replace c with that drive letter corresponding to the part of HDD/SDD that has Windows installed on it.
- Then, type ‘cd windows\system32\config’ and press Enter
- Type ‘dir’ and press Enter. The list of all files and folders will appear on the screen.
- One by one (only for each file), type ‘ren (File name) (File Name).old’ command and press Enter.
For example: Type in ren SYSTEM SYSTEM.old for the SYSTEM file in the directory, and ren SECURITY SECURITY.old for the SECURITY file in the directory.
- After renaming each file (creating backups of all), type ‘cd RegBack’ in cmd and press Enter
- Type dir’ and press Enter. The names of all files and folders will appear.
- Now, you need to type the following commands in cmd one by one:
copy /Y SOFTWARE
copy /Y SAM
copy /Y SYSTEM
and any other folder that was renamed. After that, we will now put the registry hives back for the folders we renamed.
Once the process is done, close the command prompt by typing Exit and pressing Enter. Then, remove the Windows installation media and restart the computer. And see if it boots up without running into the 0xc000021a error screen.
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