How to Fix Windows 10 Error 0xc000021a

How to Fix Windows 10 Error 0xc000021a

This is a common BSOD error which occurs when WinLogon or (CSRSS) Client Server Runtime Subsystem are causing a BSOD or it could be Winlogon or CSRSS are corrupted. You can also get this error from a corrupt or failed Windows update. This error code 0xc000021a can also point towards Malware. The error will cause can continuous boot loop. I will show you things you can try to fix the error 0xc000021a.

* Corrupt operating system files.
* There was a failed Windows upgrade.
* Corrupt Windows Update
* Incomplete installation of a software program.
* Malware

I hope these resolve your error.

1. First, try a system restore.
2. chk disk /f /r
3. sfc /scannow
4. dism/online/cleanup-image/restorehealth
5. dism /image:C:\ /cleanup-image /revertpendingactions
6. Disable Driver Signature Enforcement
7. Try booting to safemode with networking
8. Roll computer back to a previous version of Windows
9. Restore files from RegBack folder ( I have made video on how to do this)
10. When all else fails try Reset your PC

If you need any more help please join my forum

[zachpoole]

I can't tell you how grateful I am that you took the time and effort to make this video for the general public, without expecting anything in return :) i had resigned myself to losing my data and resetting my PC, but i found this video, and thought you seemed very friendly and very knowledgeable so i gave all your suggestions a try. it actually was literally the final one that worked for me and fixed the problem - disabling driver signature enforcement. i just wanted to say i'm really appreciative that people like you make the effort to help people you'll never meet - that's the way the world should work, us helping one another out. my sincere gratitude to you my friend.

[leosypher]

It's funny how every place I've visited thus far for this issue, when ever there's a command they say "here's the command to copy and paste"
You realise you just told me to copy paste a command to fix and issue that doesnt let me boot my computer, right?

[MilanPutnik]

This is an old computer Master - I've been growing up and learning having such ones by my side.
I am now a computer scientist.
Thank you for this !

[dewaynewinters]

What if I cant get tto anything. Blue screen with code shuts my computer down everytime

[txctamizhan]

I am just getting "unable to access the image" is appering

[ModeratelyInsane]

it's ridiculous that i have to do this stuff in 2018... feels like trying to run a linux distribution

[niltongaviao]

Thank you very much you saved me a bunch of neurons. You were simple and went straight to the point, that is what people in trouble need. Thank you again.

[beckivideo]

I'm surprised to have been faced with this issue on a new Dell XPS 15 in 2020. I tried every single option in the "choose an option" menu, and even Dell support couldn't help me. The first fix in this video did the job perfectly, I wish I had come across this video first. Thanks! :)

[brobenjoyer]

This was extremely helpful for me. It's sometimes hard to sift through all the tutorials you find on all the variety of PC issues. I'm glad I started here. Thanks a million.

[CyberChaos]

Seems like later versions of Windows 10 doesn't support the "dism" command

[nityasingh]

Those who are getting error 87 or any other error after typing the command
MIND THE SPACES IN BETWEEN THE CHARACTERS specially between \ and /
the exact command is :
dism/image:c:\(space between

[Bburner]

The fact that my doing a system restore back to May 1, 2020... only 3 days later on May 4, 2020; shouldn't have caused all this!
What drivers, updates, etc. could I have possibly undone and made my computer unstable in just 3 lousy days? This is maddening!

[WalnutSpice]

I've been running the same windows 7 install on a western digital 500gb drive since 2014 with no issue. Now I slap in an SSD, throw windows 10 on it to try it out. Got a blue screen after installing java that stopped me from booting, fixed it, install windows update, now I'm here again. Windows 10 is a joke.

[sunnylightning]

Went through all the command prompts, and did the signature enforcement restart. Wow, what a lifesaver! Thank you!!
(Windows 8)

[musgrada]

I followed all the steps given, and it wasn't until after I enabled safe mode with networking, and then did disable driver signature enforcement that I got the pc to boot. Great video!!! Very helpful!!!

[Craze_Lifter]

My Dell Inspirion 2014 model encountered this. I followed this tutorial, which took about 30 minutes and my laptop works now. Thanks.

[scomputers]

Thanks Bri, I have used this successfully on a number of occasions. Sadly I have also found that it doesn’t work the majority of time for me, although I appreciate that’s not your fault 😂😂. Just as a matter of fact, I have been fixing PCs for many years and have found Windows 10 to be the most unstable operating system I have ever worked with. The sheer amount of bsod faults that come to me following a Windows update is staggering. Microsoft in my opinion, seem to have lost the plot and I can’t understand why there haven’t been masses of class action lawsuits. How many people globally have woke up one morning to find their machine has updated and broken in the process. It’s mind boggling how like others have said, we are still seeing this in 2020. I also use an iMac and although Apple are also having their issues, my 2011 iMac has run for nearly 10 years without a single crash. If I could I would ditch Windows altogether.

[Arktag]

I was able to get in via disabling the driver signature option. None of the cmd prompt codes worked. So im confused what I do at this stage. All i did was install updates. Do i uninstall all my windows updates and try again? Cause the only way i can boot is disabling the driver signature.

[EAprima]

Thank you. This worked so far on my laptop. Received the same error code, went into Command Prompt, inserted the line you highlighted, pressed continue to Win 10 and it loaded successfully.
I will bookmark this video page for safety. Thanks again.

[gregnixon]

Going through all of the checks takes a LONG, LONG time. I am hopeful that this will fix my problem. I am thankful for this video. It gave me somewhere to start in the repair.