How to fix installation error 0xc000021a on Windows 10

Windows 10 installation issues, or to be exact ”BSoD-inflicting errors” are quite rare. However, once you bump into the installation error like 0xc000021a, the problems intensify quite quickly. Blue Screen of Death can mean a lot of things but nothing good, so you can rest assured that this is a grave issue.

The gravity of this error means that’s hard to address it, especially if you already formatted your system partition before the error occurred. We can only suspect what is the reason for this critical error, so we presented various solutions below in order to tick all the boxes.

If you’re stuck with this installation issue and unsure how to move on and resolve it, make sure to check the steps below.

How to address installation error 0xc000021a on Windows 10

1. Create bootable drive again with genuine Windows
2. Unplug all peripheral devices
3. Upgrade trough OS
4. Run SFC
5. Rebuild BCD
6. Disable Driver Signature Enforcement
7. Check HDD health

Solution 1 – Create bootable drive again with genuine Windows

First things first. If it’s in your capacity to try reinstalling Windows 10 on an alternative PC, make sure to give it a try. That’s the best way to check is your ”bootable” drive bootable in the first place. The procedure is the same for both DVD or USB thumb drive, meaning that, if you’re able to boot on at least one PC, the problem lies in the other PC and the installation drive is probably properly configured and created.

On the contrary, if you’re unable to boot on any given device you’ve tried to, make sure to create the bootable drive with the Windows 10 installation from the scratch and try booting again. If you’re not sure how to do it properly, follow these steps:

USB

1. Download the Media Creation Tool from here.
2. Plug in the USB flash drive with at least 4 GB.
3. Run Media Creation Tool and accept the License Terms.
4. Choose ”Create installation media (USB flash drive, DVD, or ISO file) for another PC”.
5. Select the preferred language, architecture, and edition.
6. Click Next.
7. Choose USB flash drive and click Next.
8. Wait until the installer downloads the files and, finally, you’ll have a properly created and configured bootable drive with Windows 10 installation.

DVD

1. Download the Media Creation Tool from here.
2. Run Media Creation Tool and accept the License Terms.
3. Choose ”Create installation media (USB flash drive, DVD, or ISO file) for another PC”.
4. Select the preferred language, architecture, and edition.
5. Click Next.
6. Select ISO file.
7. Save the ISO file to a preferred location and wait until the download completes.
8. Insert DVD and use any third-party burning tool to create the bootable Windows 10 DVD.

Solution 2 – Unplug all peripheral devices

Another possible culprit that can certainly cause critical system errors involves peripheral devices. Peripheral devices can occasionally cause a stall in the loading process. Furthermore, that halt can lead to more than a few errors, including the Blue Screen of Death crash with the ”0xc000021a” error code that comes along.

So, make sure to leave only the mouse, keyboard and monitor plugged in while booting from USB or DVD. You should disable everything else just in case one of the secondary devices are preventing the Windows 10 installation process to commence.

On the other hand, if you’re still unable to boot, make sure to check the additional steps.

• ALSO READ: Fix: Mouse Cursor Disappeared in Windows 10

Solution 3 – Upgrade trough OS

With the introduction of Windows 10, users are offered multiple choices when it comes to upgrading. By using the Windows Media Creation tool, you can upgrade to Windows 10 without deletion of the current system. How does this exactly resolves your problem?

Well, some users managed to resolve the issue by installing older Windows iteration and than upgrading to Windows 10 with Media Creation Tool. For no apparent reason, this helped them overcome the boot error that plagues so many Windows users.

If you’re not sure how to do it, follow the steps below and we should be good to go:

1. Download Media Creation Tool by following this link.
2. Run Media Creation Tool and accept the Licence Terms.
3. Choose Upgrade this PC and the downloading process should commence.
4. Once it downloads files, Media Creation will start upgrading.

Solution 4 – Run SFC

Sometimes, the corruption of system files can lead to a world of problems in many departments, including Windows 10 reinstallation. Due to virus infection or integrity issues, certain boot files can get corrupted which will, eventually, result in a critical system error. Just like the installation error that bears the 0xc000021a code.

There are various ways to address this, but the best way to overcome this and similar issues is to use System File Checker and scan for errors. In addition, it’s highly recommended to perform a full scan with a third-party antivirus in order to get rid of the malware infections. Once you’ve dealt with the malicious software, follow the steps below to utilize the SFC tool:

1. Right-click the Start menu and run Command Prompt (Admin).
2. In the command line type the following command and press Enter:
   • sfc/scannow
3. Wait for the scanning procedure to end and look for improvements.

If this wasn’t enough, make sure to continue with the additional solutions we presented below.

• READ ALSO: No boot screen on Windows 10? Here’s how you can fix that

Solution 5 – Rebuild BCD

In case that your PC is unable to read the installation setup in the repeated sequence, there’s a chance that the boot sector is deleted or corrupted. If you want to address this, you’ll need to rebuild the Boot Configuration Data and repair boot sector.

In the preferred scenario, after you rebuild BCD, the installation files should load seamlessly so you can finally move to reinstallation process.

If you’re not sure how to do it, follow the instructions below:

1. Insert the Windows 10 bootable media (USB stick or DVD) and restart your PC.
2. Set USB/DVD as primary boot device. Either by entering the Boot menu (F10, F11, or F12) or from the BIOS settings.
3. The loading process of the installation file should commence.
4. Select the language, time/format, and keyboard input of choice and click the ”Next” button.
5. Select ”Repair your computer” from the bottom left corner.
6. Open the Troubleshoot option.
7. Select Advanced Options.
8. Open Command Prompt. Select your account and enter the password if asked.
9. In the command line, type the following commands and press Enter after each:
   • bootrec /FixMbr
   • bootrec /FixBoot
   • bootrec /ScanOs
   • bootrec /RebuildBcd
10. This should finalize the repair procedure and you should be able to start Windows 10 installation setup just as intended.

Solution 6 – Disable Driver Signature Enforcement

Besides booting in Safe Mode as a recovery or troubleshooting option, you can change other boot elements in order to troubleshoot certain issues with Windows 10. One of those is disabling of Driver Signature Enforcement that’s, in a simple manner of speaking, a security measure that blocks drivers that aren’t digitally signed to run in Windows 10.

However, sometimes you might need unsigned drivers in order for things to work and there the above-mentioned disabling of Driver Signature Enforcement comes in handy. If you’re not sure how to do it, follow the steps below:

1. Open Start.
2. Press and hold Shift, click on the Power button, and select Restart.
3. Your PC should boot in the Recovery options menu.
4. Select Troubleshoot.
5. Choose Advanced options.
6. Select Startup settings.
7. Choose Restart.
8. One the PC restarts, press F7 to select Disable driver signature enforcement.
9. Insert the installation media and look for changes.

Solution 7 – Check HDD health

Finally, if none of the aforementioned steps worked for you, maybe your HDD is causing the error in the first place. What you can do in this scenario is to run HDD diagnostics and check for bad sectors or defects. You can use various third-party tools, but there’s the Windows alternative. For this purpose, you can use the ”Check for errors” tool and find out the exact state of your HDD drive.

If you’re uncertain how to do it, follow the steps we provided below:

1. Open This PC or File Explorer.
2. Right-click on the system partition and open Properties.
3. Select the Tools tab.
4. Click on the Error checker tool and wait for the procedure to finish scanning.

However, if you’re more into details, maybe you can use one of 14 HDD diagnostics and monitoring tools we enlisted in this article. We highly recommend to check it out.

We certainly hope that this was a helpful read and that you’ll be able to overcome the installation error with the hex error code ”0xc000021a” in Windows 10. 

Additionally, make sure to share your questions or suggestions regarding this and similar installation errors in the comments section below.

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