Any Windows System file is important for the smooth functioning of the Operating System. If any file goes missing or gets corrupted, your system will have difficulties performing the necessary tasks. One particular system file that gets attacked by viruses a lot is the cng.sys file. The cng.sys file loads up every time you turn on your Windows system. But if you see “cng.sys failed/ missing error” whenever you turn on your PC, then that file is either corrupted or deleted from your system.
One common issue you will encounter when your cng.sys file is missing is the Blue Screen of Death. Some users repeatedly got the Blue Screen of Death again and again whenever they turned on their system. Switching to the Safe Mode from the boot menu works as a temporary solution to keep using the system. But for a permanent solution, you will have to follow the guide mentioned below. Here, we have listed all possible solutions to fix the cng.sys file error. So without further ado, let’s get into it.
How to fix the cng.sys file missing/ failed error on Windows 10?
The reason behind the cng.sys file missing error could be a virus attack, in which case more than just the cng.sys file will stop working in your system. Or you might have faulty memory due to some sectors of the memory going bad. There is also a chance that you might have unsupported or faulty hardware installed in your system. Or maybe your registry has some corrupt files, or your drivers are not updated. These are all the possible reasons why one might be facing the cng.sys file error. But for any of this to happen, your system must have gone through a change recently. It may be a hardware or software alteration.
If you are not sure what could be possible behind this blue screen of death error, then try all the solutions mentioned below, one after the other. Undoubtedly, one of them will work out the trick for you.
Restore to an earlier version of Windows:
As mentioned above, you will see the cng.sys error on your system only if had gone through any change recently. You might have installed a new Windows update, and now you are stuck with the Blue screen of death. You can revert your system to what it was by restoring everything to an earlier version.
- Press and hold Windows Key + X and choose “Settings” from the list of options.
- Click on “Updates and Security.”
- Then click on “Recovery.”
- Under “Go back to the previous version of Windows 10,” click on “Get Started.”
- Follow the on-screen instructions and complete the process of going back to a previous build of Windows.
This method would fix the issue right away if you started facing the problems following a Windows Update. But to be able to use this feature, you need to try this method within 10 days after installing the new update. 10 days later, this method won’t work at all, and the “Get Started” will be blacked out. So if you are already past the initial 10 days, then move on to the next solution mentioned below.
Scan your entire system:
We have mentioned above that one of the reasons why the cng.sys might go missing is because of a virus attack. So if you think that your system is infected, then perform a full system scan for infection. We suggest you use an antivirus program with the latest update definitions installed on it. Outdated definitions will only mean that your antivirus won’t detect any new kind of viruses. Also, don’t go for a quick scan. Instead, go for a full system scan as a quick scan skips many data sections to keep the scan minimal. Sometimes it even skips system files, which is something we don’t want.
If the scan does not reveal any infection, then move on to the next potential solution.
Install any pending updates:
Windows releases new builds or versions of Windows 10 now and then to keep the system error-free and bug-free. So if you have any downloaded updates pending for installation or have not yet downloaded the latest release, then download it right away and install the latest version on your system. If it was a bug that was causing this error on your system, then it will be wiped out, and you will be able to use your system like you normally do.
If you are already using the latest version, or the update did not fix your issue, try the next solution mentioned below.
Run a disk check:
You should also perform a disk check on the disk that has all your Windows files. Usually, we install the Windows files on to the Disk C.
- Right-click on the disk where you have installed your Windows 10.
- Choose “Properties.”
- Click on the “Tools” tab.
- Under “Error Checking,” click on the “Check” button.
- Click on “Scan drive” and then follow the on-screen instructions to complete the scan process.
If the error checking process does not fix your cng.sys error, then move on to the next potential solution.
Run the SFC scan:
System File Checker is a quick scan that checks whether all the Windows system files on your system are working fine. If there is any file missing in your directory, or maybe the file is corrupted, then System File Checker will try to fix it for you.
- Click on the search bar and look for “Command Prompt.” Once it shows up in the results, click on “Run as an administrator.”
- Click on Yes when the UAC pop-up shows up.
- In the command prompt window, enter “sfc/scannow” and press the Enter key.
Once the process is complete, check if you get the same cng.sys file missing error again. If you do get the error, then try the next solution.
Perform a Startup Repair:
If you have installed a new application, or maybe new hardware, and you are witnessing the error after that, then uninstall that application or remove that piece of hardware right away. And then perform the startup repair from the “Advanced Startup Options” menu.
- Restart your computer.
- When the system starts booting up again, press the F8 button continuously, and it will open up the Advanced Startup Options menu.
- Now choose “Repair Your Computer.”
- Finally, click on “Startup Repair” and then follow the on-screen instructions to complete the process.
If the system repair does not do you any right, move on to the next solution mentioned below.
Update your drivers:
Outdated drivers are the cause of many Windows system errors. Getting a blue screen of death error is common if you have issues with your system’s driver files. So you have to update every driver that you feel is outdated. To update the drivers, you can either use a third-party application that scans all your drivers and installs a new version of it if it is out there. Or you can manually choose to update the drivers one after the other by accessing the “Device Manager” window in Windows.
- Press and hold Windows Key + X and choose “Device Manager” from the list of options.
- Double click on any category in the Device Manager window to expand it.
- Right-click on any one of the subcategories and click on “Update Driver.”
- Follow the on-screen instruction to complete the installation of the new drivers.
After you are done updating your drivers, if you still encounter the cng.sys file missing error, try the next solution.
Use the system in Safe Mode:
Using a Windows system in Safe Mode limits its functionalities. When your system loads up in Safe Mode, most of your driver files are not functioning, and your default settings are also ignored. So if you see the cng.sys file missing error again and again, then reboot your PC in Safe Mode. If it loads up correctly this time around, you have narrowed your probable cause to a faulty driver. In that case, to fix the error, you need to uninstall that specific driver.
To boot your system in Safe Mode,
- Press and hold Windows Key + X and choose “Settings” from the list of options.
- Click on “Updates and Security.”
- Then click on “Recovery.”
- Under Advanced startup, click on “Restart now.”
- Your system will start restarting right away.
- Once it boots up, select “Troubleshoot” on the Choose an option page.
- Then click on “Advanced options.”
- Choose Startup Settings after that, and then click on the Restart button.
- When your computer restart, a list of options with numbers will show up.
- You will see option 4 as Safe Mode. Press the 4 key, and your system will boot up in Safe Mode.
As expected, if you don’t see the cng.sys file error while your System is in Safe Mode, then it is definitely a faulty device or driver causing the issue. Find the device in question by going into the Device Manager window.
- Press and hold Windows Key + X and choose “Device Manager” from the list of options.
- Double click on any category in the Device Manager window to expand it. This particular error occurs mainly due to the graphics drivers. So open up the display adapter category and check if there is an exclamation mark next to your drivers.
- If there is one, then right-click on it and choose Uninstall.
- After uninstalling the problematic driver, restart your system and download that driver from the manufacturer’s official website again. This time make sure that the driver is properly installed and there is no exclamation mark next to it in the Device Manager window.
To exit the safe mode,
- Press and hold Windows Key + X and choose “Run” from the list of options.
- In the Run dialog box, enter “msconfig” and press the Enter key.
- A pop-up window will show up. Click on the Boot tab.
- In the Boot tab, deselect “Safe Mode” and click on Ok.
- Now restart your computer, and it will load up normally.
If even this does not solve your problem, then you are probably missing some of the important Windows System files. In that case, the only option you have is to reinstall Windows into your computer.
Perform a Clean Reinstall of Windows:
When every other solution fails, then Windows reinstallation is the only option left with you. Before reinstalling every system file, it would be best to backup anything important to you. Plug in an external storage device and move everything important to you from the system drive onto that external drive. If booting up normally does not let you do the backup, then boot into the Safe Mode mentioned above in the previous solution. After you are done making a copy of everything necessary to your external device, insert a bootable CD or USB drive into your computer. Restart your computer, and the Windows installation will take over your system. Follow the on-screen instruction and format your entire system drive. After formatting, continue with the process and complete the Windows installation.
Windows reinstallation will mean that you will have to set up everything up like you did when you first got Windows in your system. It will take a while to get your system configured back to what it was before the error showed up. You will obviously have to reinstall every driver and program again, as the format will delete everything installed on your system. Once that is done, you can go on about using your PC like you normally do.
So that is all about fixing the cng.sys file missing/ failed error in Windows 10. If you have any questions or queries about this article, then comment down below, and we will get back to you. Also, be sure to check out our other articles on iPhone tips and tricks, Android tips and tricks, PC tips and tricks, and much more for more useful information.