When any system error occurs on your computer with Windows 10, the very first thing you need to do is to use System File Check. This mechanism was specifically designed for analyzing and logging data concerning the most important elements of the system. Furthermore, it also has functionality that allows the app to fix most non-critical errors.

If you have manually modified some system files on your computer (including DLLs), System File Check will revert the files to the original state. This is what you need to do:

1. Press Win+X.

2. Find the line Command Prompt (Admin) and click it.

Context Menu

3. In the window that will appear type sfc /scannow and press Enter.

sfc

4. Wait until system scan is over. It might take several minutes to complete.

scan entegrity

On the screenshot above, we can see that the tool didn’t find any problems with the system. But if you are not so lucky, the message may be different, informing you that not everything is ok:

  • System File Check found corrupt files and restored them. In this scenario, we would recommend you to initiate another scan right away just to be sure that everything is good now.
  • System File Check found corrupt files but was unable to restore them. In this case, you need to restart the process again as well. If the problem is still present, you can try another method from this article written in the next paragraph.

How to fix System restore could not start error?

When you are executing the scannow command from the previous paragraph, another error might occur – «System restore could not start.» You can fix it by doing the following steps:

1. Press Win + R.

2. In the window that will appear type services.msc and press Enter.

services.msc

3. In the next menu look for the Windows Modules Installer and double-click it.

services

4. Set its startup type to «Manual». Press the Start button, then Apply button.

Manual Setting

5. Close the Services window.

If this method does not help, read the next paragraph of this guide.
 

Repair Windows 10 using DISM

After failing to recover corrupt files using System File Check, don’t fall into despair because there is another way to fix the problem with the more advanced utility tool designed for file recovering and repairing in Windows 10. It is called DISM (Deployment Image Servicing and Management tool), and this is how you can use it:

1. Press Win+X.

2. Find the line Command Prompt (Admin) and click it.

3. In the window that will appear type DISM /Online /Cleanup-Image /RestoreHealth and press Enter.

DISM

4. Wait until for DISM to complete scanning and fixing error it finds in the process. Usually, it takes from a few minutes to half of an hour.

If DISM finishes the scan successfully, we recommend you to go back to the beginning of this guide and initiate System File Check once again. In case DISM scan goes wrong and errors occur in the process, then you will have to use another method described at the very end of this article.
 

How to fix DISM could not find source files error

Sometimes during DISM scans an error occurs, and that informs the user about DISM was unable to find source files. It means that the recovery service has no temporary files to complete the procedure. Solving this problem may take a lot your time, but it gets the job done:

1. Download official Windows 10 ISO that matches the version of Windows you are using right now.

2. Integrate into this image the latest Windows update you have installed on your PC. For example, if you are using the 14393.970 build, while you have downloaded earlier build, you need to integrate the newer build. Otherwise, system recovery won’t work as intended.

3. Create a bootable USB drive.

4. Open Command Prompt (Admin) and type the command: DISM /Online /Cleanup-Image /RestoreHealth /source:WIM:X:\Sources\Install.wim:1 /LimitAccess (where X – is the letter of your bootable USB flash drive).

DISM

5. Run DISM file recovery again.

As you see, these actions might take a lot of your time, and it is not as easy as the other methods we have covered already in this guide. Therefore, you might want to use another method we saved for the end.
 

System Restore in Safe mode

There is a possibility that running your system in Safe Mode (minimal configuration with only essential system programs) will help DISM and System File Check tools to restore your system files.

  • Run Windows 10 in Safe Mode (boot option should be set to Minimal).
  • Complete all the steps using SFC and DISM tools we mentioned in the corresponding paragraphs of this guide.

How to restore all system files?

If all other methods failed to help you, then it is only one way to deal with the problem. Please note that screenshots we created might be different from what you see on your screen due to Microsoft’s updates of their Media Creation Tool (can be downloaded on the official website). However, the steps are the same:

  1. Download official Windows 10 ISO image (its version must match the one you are using right now).
  2. Integrate your latest Windows updates into this image (it is not necessary but we still strongly recommend you to do so).
  3. Create a bootable USB flash drive or burn a disc with this image.
  4. Insert your USB flash drive into your computer.
  5. Run the setup.exe file from the flash drive.
  6. Wait for the program to check your PC, download updates, and apply them.
  7. Read applicable notices and accept license terms.
  8. When the program is ready to install, be sure to check «Keep personal files and apps.»
  9. Wait while it makes sure that everything is ready for the installation.
  10. Click «Install.»

After the last step Windows 10 will be reinstalled on your PC (all apps, settings, and files will remain as they were). All system files will be restored to their original state. This procedure may take up to 1-1.5 hour. Don’t turn your computer off and don’t interrupt the installation process. In case even this method didn’t fix the problem, you should really think about full Windows removal and installing it again. It is still an ultimate solution to all software problems to date.