I recently upgraded my hdd for an ssd and cloned my hdd using acronis software which came with my crucial ssd. System stopped booting after i completed the installation i am seeing the blue screen error with the code 0xc000021a. I tried system restore but no restore points were available. Is this because my hdd file system was corrupted and acronis cloned the disk with the errors? How can fix this?

Update: The machine is in a boot loop. Recovery is not working as expected. Resetting the machine also failed. Tried both cloud download and local install.

  • You will have to provide us the output of the analysis from WinDBG in order to help you
    – Ramhound
    Jul 8, 2022 at 23:08
  • @Ramhound the system stopped booting showing a bsod and i am not able to enter safe mode or reset pc.
    – Khaleel
    Jul 8, 2022 at 23:45
  • From your description the SYSTEM boots and apparently loads the OS fine. It is WINDOWS that errors out with a BSOD. What did the results of your search for that error code show? I suspect you need to fiddle with TPM or secureboot settings in BIOS, or boot from a windows disc and choose "repair" or whatever they offer.
    – mitts
    Jul 9, 2022 at 2:32
  • The machine is in a boot loop. I tried recovery, reset etc.
    – Khaleel
    Jul 10, 2022 at 7:36

2 Answers 2


The stop code 0xc000021a represents the WINLOGON_FATAL_ERROR, which occurs when a user-mode subsystem, such as WinLogon or Client Server Run-Time Subsystem (CSRSS), is compromised. It additionally means that security can’t be guaranteed for your system due to this error. And in turn, the Windows Operating System (OS) switches to the kernel-mode, showing a blue screen.

Sometimes, when you restore your hard disk from a backup, the system files can be corrupted or faulty and may cause this error on your system. Other causes behind the 0xc000021a error may include a corrupted hard drive, faulty device drivers, incompatible software/app installed, and problematic Windows update. Here I am sharing with you some of the methods that you can use : How to fix the 0xc000021a error code?

Run SFC Tool

Run Windows Defender Antivirus Tool

Update/Uninstall Device Driver

Uninstall Problematic Windows Update

Run CHKDSK Command

Uninstall Incompatible Software/Application

Perform System Restore

To enter Safe Mode, follow the given steps:

Restart your system; as soon as you see the Windows logo on the screen, reboot it again and repeat this step thrice. After that, you’d reach the Automatic Repair environment. There, click ‘Advanced options’, leading you to the ‘Choose an option’ screen. There, click Troubleshoot > Advanced options > Startup Settings > Restart. Once your system gets restarted, click F4 to enable Safe Boot.

Method 1: Run SFC Utility

Press Windows + R to open the Run dialog box. Open Command Prompt and choose to run it as administrator. Then type the following command and press Enter. Now, wait for a while as it may take some time to show system files that need to be fixed. Next, type SFC/scannow command and hit Enter. Let the process complete. Once done, close the window and try rebooting your system to check if the error is gone.

Method 2: Run Windows Defender Antivirus Tool

Open System Settings and go to Update & Security > Windows Security > Virus & threat protection. The Windows built-in Windows Defender antivirus program will start scanning the PC for any viruses. If there’s a malware present on your system, it will show up in the results. Next, follow the instructions given on the screen to fix the windows stop code 0xc000021a. After completion, reboot your system and check if the problem is solved.

Method 3: Update/Uninstall Device Driver

Press Windows + X, click Device Manager and then navigate to the device category where you want to update the drivers. Expand the device category and right-click on the driver. Choose Update driver. Next, choose to ‘Search automatically for updated driver software.’ Let Windows look for the latest driver software available. If you already have the latest driver, try uninstalling it and then re-installing it with the compatible one.

Go to the device driver, which seems to be causing the issue, and right-click on it. Choose Uninstall device. On the next prompt, click ‘Delete the driver software for this device’ and click Uninstall. Wait and let the process end. Now, close the window and check if the error is gone. Afterward, you can download the compatible device driver by visiting their manufacturer’s site.

Hope all these steps will help you out


This is a common problem while cloning hard drives using acronis. Though the acronis knowledge base suggests to insert the ssd in the laptop, boot from a bootable acronis media and clone the hdd connected through usb. This method also did not work for me. There was something wrong with UEFI settings associated with the drive. You may rebuild BCD settings to fix boot issue. I got this idea from this page

Make sure you backup your data before attempting the instructions in the page.

Following are the steps.

  1. Boot from a windows bootable media
  2. Goto repair your computer
  3. You need to mount the EFI partition next. Type diskpart
  4. Type list disk to list all disks
  5. select disk <your disk number> to select the primary disk
  6. list volume to list all volumes
  7. select volume <volume number of efi partiotion> to select the EFI patition. Normally this should be the hidden FAT partition named SYSTEM
  8. assign letter=T: to assign a drive letter. Use a free drive letter.
  9. exit to exit diskpart
  10. Now mount the EFI partition by typing the drive letter assigned. T:
  11. Now format the EFI partition format T: /FS:FAT32
  12. Now type bcdboot C:\windows /s T: /f UEFI to rebuild BCD.

At this point my problems were solved. You may try the following also.

bootrec /FixMbr
bootrec /FixBoot
bootrec /ScanOs
bootrec /RebuildBcd

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