If you are having trouble booting into the desktop, facing random errors, or some features stop working properly on Windows 10, it’s most likely a result of corrupted or missing system files. Generally, system files can get corrupted after installing a buggy cumulative patch, driver, or making wrong registry edits.
A single corrupted system file may bring your entire workflow to a halt, so it’s crucial for you to repair Windows 10 immediately. Chances are you have come across a similar issue, which has brought you here. Thankfully, you can use Windows 10’s System File Checker or SFC command-line tool to scan your PC and repair corrupted or restore missing system files to get everything working normally again.
This guide will show you the way to fix corrupted system files on Windows 10 using the built-in System File Checker tool.
Repair Windows 10 with System File Checker
In order to repair your Windows 10 installation using the System File Checker tool, follow the steps below. Though before you proceed, make sure to back up your important files if you have the option.
- First, right-click the Start button and select Command Prompt (Admin) from the following contextual menu.
- Type the following command in the CMD window and press Enter to launch the SFC tool:
- Now, wait for the SFC tool to scan your system and find missing or corrupted files. You will get one of the following results once the process completes:
- Windows Resource Protection did not find any integrity violations: It means that there are no corrupted or missing files in your system.
- Windows Resource Protection could not perform the requested operation: If you get this message, you will need to run an offline scan.
- Windows Resource Protection found corrupt files and successfully repaired them. Details are included in the CBS.Log %WinDir%\Logs\CBS\CBS.log: It means the SFC tool detected the problems and was able to fix them successfully.
- Windows Resource Protection found corrupt files but was unable to fix some of them. Details are included in the CBS.Log %WinDir%\Logs\CBS\CBS.log: Those who have received this message must repair or replace the corrupted files manually.
If you can’t run the SFC tool via Command Prompt, consider using the DISM (Deployment Image Servicing and Management) tool to repair any corruption problems that can prevent SFC from running. Simply open a CMD window as administrator and perform the following command:
DISM /Online /Cleanup-Image /RestoreHealth
It’s worth mentioning that the repair process might take several minutes to finish. If the process appears to be stuck in one place, don’t close the window and give it some time to complete.
Steps to view the System File Checker logs
If you want to check out the details stored in the CBS.Log file generated from an SFC scan, use the below steps:
- Right-click the Start button and choose Command Prompt (Admin) in the context menu. Make sure to click Yes when the UAC prompt appears.
- Next, run the following command in the Command Prompt window:
findstr /c:"[SR]" %windir%\Logs\CBS\CBS.log > C:\sfclogs.txt"
- After that, open File Explorer from your desktop. You can also press the Windows key + E on the keyboard to launch it.
- Choose This PC from the left sidebar of the Explorer window, then go to the Local Disk (C:) drive from the “Devices and drives” section.
- On the next page, double-click to open the sfclogs.txt file in Notepad or your default text editor.
Upon completing the steps, you should see all the system files the SFC tool scanned earlier, with detailed info on which ones are unrepairable. While you are in the editor, use the Find option (Ctrl + F) and search for the “Cannot repair member file” sentence to determine the corrupted files requiring replacement.
Note that you can access the log only when running the System File Checker within Windows 10 and not when running an offline scan with Command Prompt. More on that in the next section.
Run offline SFC scan on Windows 10 to repair system files
You can use the System File Checker tool on Windows 10 offline to repair corrupted or missing system files. These steps will show you how to do it:
- First, open the Start menu and launch the Settings app from the sidebar.
- Go to the Update & Security page and choose Recovery in the sidebar.
- Next, click the Restart now button under the “Advanced startup” option.
- After your PC or laptop boots into the Advanced startup options menu, click the Troubleshoot button.
- Select Advanced options on the next screen, followed by clicking the Command Prompt option.Your Windows 10 device will now reboot once again.
- Once you are back in the Advanced startup options menu, choose your user account, confirm the password, and click Continue.
- When the CMD window appears, type the following command and press Enter to run the DiskPart tool.
- To pinpoint the location of the Windows 10 installation directory and “System Reserved” partitions, run the following command:
- Note down the drive letter for the Windows 10 partition (usually the one taking up a lot of storage space) and System Reserved partition (typically close to 500 MB).
Once you are done, type this command and press Enter to close DiskPart:
- After that, run this command to launch the System File Checker tool offline:
sfc /scannow /offbootdir=SR-DRIVE-LETTER:\ /offwindir=C:\Windows
In the above command, replace SR-DRIVE-LETTER with the drive letter of the “System Reserved” partition, which happens to be F in our case. Windows is usually installed in C: drive, so you probably won’t have to change it.
Once you finish the steps, SFC will scan for problems with the Windows 10 system files and fix them offline. When it’s done, you can safely close the Command Prompt window, then click Continue to restart your device.
Repair Windows 10 manually without the SFC tool
The System File Checker in Windows 10 can’t always fix corrupted or restore missing system files. In that case, you must repair them manually. Here’s how:
- Follow the instructions in the “Steps to view the System File Checker logs” section above in this guide. The SFC log file will tell you which system files are unrepairable and need replacing.
- Next, you need to find the actual location of a corrupted system file, which should be a few clicks away from a Google search.
- Copy the healthy version of the system file from another machine to yours. Note that both devices must be running the exact version and edition of Windows 10.
- Now launch a Command Prompt window as an administrator on your PC or laptop.
- To take full ownership of a corrupted file, run the following command:
takeown /f C:CORRUPTED_FILE_PATH
In the above command, replace CORRUPTED_FILE_PATH with the path of the corrupted system file you want to repair manually. Here’s an example that takes ownership of the “acppage.dll” file:
takeown /f C:\Windows\System32\acppage.dll
- After that, perform the following command to get full admin access to the corrupted file:
icacls C:\CORRUPTED_FILE_PATH /Grant Administrators:F
Once again, replace CORRUPTED_FILE_PATH with the path of the corrupted file you want to fix. Here’s an example that gets you full administrator access to the “acppage.dll” file:
icacls C:\Windows\System32\acppage.dll /Grant Administrators:F
- To replace the corrupted file with a healthy version of it, run the following command in the CMD window:
copy C:\HEALTHY_FILE_PATH C:\CORRUPTED_FILE_PATH
In the above command, make sure to replace HEALTHY_FILE_PATH with the path of the healthy system file. Similarly, replace CORRUPTED_FILE_PATH with the path of the corrupted system file.
Here’s an example that replaces the “acppage.dll” file in the Windows System32 folder:
copy C:\Healthy files\acppage.dll C:\Windows\System32\acppage.dll
- Once you do that, verify the integrity of the replaced system files using the following command:
- (Optional) To verify the integrity of a particular system file, use this command:
Make sure to replace SYSTEM_FILE_PATH with the path of the file you replaced earlier. Here’s an example:
And that’s it! If the replaced system files go through the integrity check without any errors, you most likely have fixed the issues you had before in Windows 10.
If you are unable to repair the corrupted system files on Windows 10 using the System File Checker tool, we recommend reinstalling the operating system to start fresh.