The full error message for this error code can be seen below-
Possible causes
On investigating the issue and coming across different symptoms of this error, we narrowed it down to four culprits that might trigger the 0xc0000221 error code, as listed below: The operating system couldn’t be loaded because the kernel is missing or contains errors. File:\WINDOWS\system32\ntoskrnl.exe Error Code: 0xc0000221.
Kernel ntoskrnl.exe is missing or contains errors, Error code 0xc0000221
We have provided some troubleshooting steps to help you remediate the 0xc0000221 error code. Below you have a collection of potential fixes that can aid you to successfully getting the issue resolved. We recommend you try the fixes in the order that they have been presented. Let’s dig into the practical aspect of applying these solutions. IMPORTANT: Whatever may be the reason, your priority should be to try and enter Safe Mode. If you can get into Safe Mode, great; else, you will have to use your Windows Installation Media.
1) Boot into Safe Mode
While in Safe Mode, your computer will start in a limited state with only the basic files and drivers needed for the Startup process. If your computer boots just fine into Safe Mode, then it’s likely the issue is been triggered by some software you previously installed. Below is what you need to do, to troubleshoot this error once you have successfully booted into Safe Mode: If you are unable to get past the startup screen, you can force the Advanced Startup Options screen by boot interrupting (Power on the PC, power off when the Windows logo appears. Repeat 2 or 3 times, always powering off when the Windows logo appears) the startup process. If you are able to complete the booting process, you can also open the Settings Recovery tab by opening a Run dialog (Windows key + R) and typing ms-settings:recovery, hit Enter. Then, simply click the Restart now button under Advanced startup.
Once you get to the Advanced Startup Options screen, select Troubleshoot and then click on Advanced options. Inside Advanced options, click on Startup Settings, and then click the Restart button.
When you get to the Startup Settings again, press F4, F5 or F6 to boot with one of the three Safe Modes available. If your computer boots successfully into Safe Mode, it’s safe to say the diagnosis, is a service from an application that you recently installed is triggering the error. In which case, you can start uninstalling recently installed programs that you feel could be causing the issue or, you can try to systematically exclude programs and services from the startup process until you manage to find the culprit. But if you got the same 0xc0000221 error while booting in Safe Mode, proceed with the next fix below.
2) Perform an SFC, CHKDSK and DISM scan, in that order
By running these three built-in utilities designed to fix Windows file corruption, you can eliminate the possibility that the 0xc0000221 error code is not occurring due to a system file or file system corruption. Below is how you can use these utilities to troubleshoot this error: You begin by running the System File Checker. If you are unable to get past the startup screen, follow steps outlined above to get into the Advanced Startup Options menu, then go to Troubleshoot > Advanced Options > Command Prompt. Then, type the command below and hit Enter to run the System File Checker. Once the sfc/scannow process is complete, restart your computer and see if the error persists. If it still is, return to an elevated Command prompt as shown above, and type in the following command and hit Enter, to run CHKDSK: Note: In the above command, if your Windows 10 installation is not residing on the C drive, change the letter accordingly. When the procedure completes, reboot PC and see if you can get past the startup screen. If the same error repeats, return to the elevated Command Prompt as described above and copy and paste the following command and hit Enter, to run the DISM scan: Once this process completes, restart your PC and see if it boots without the error. Still not resolved, you can try the next fix. Fix: NTOSKRNL.exe BSOD on Windows
3) Verify RAM for issues
You can verify if your installed RAM modules are triggering this error. To do so, simply open up your PC and remove one of the modules (if you’re using two RAM sticks). If your PC boots successfully with only one RAM stick, try swapping the position of the two RAM sticks – issues sometimes occur when the faster memory is placed behind the slower memory. Additionally, you can run a MemTest on both RAM sticks. If you confirm your RAM modules isn’t triggering this error, you can proceed with the next fix.
4) Remove secondary GPU and external HDDs/SSDs
Here, simply disconnect every unnecessary device – secondary HDD, external HDD, DVD optical drive, second GPU from SLI (or CrossFire setup), non-critical peripherals. Once you have stripped your PC to the barest minimum, power up your PC and see if it boots successfully. If it boots without the error code 0xc0000221, systematically re-connect the non-essential components until you manage to identify the culprit. If this fix doesn’t remedy the issue, proceed with the next fix.
5) Perform System Restore
You might start experiencing this issue right after installing a Windows Update. In which case performing a System Restore could resolve the issue. If you don’t have an appropriate System Restore point or the procedure failed, you can proceed with the next fix.
6) Perform a Windows 10 OS repair install
If at this stage you’re still unable to resolve the 0xc0000221 error, you can repair install Windows 10 – this will retain your personal files, settings and applications. That’s it folks. All the best!
