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SFC /scannow Found Corrupt Files but Was Unable to Fix Some of Them – how to fix (Windows 10/11)”

January 16, 2026

The System File Checker (SFC) tool is one of the first things you should try when Windows 11 or Windows 10 starts misbehaving. Running: sfc /scannow scans all protected system files and attempts to repair or replace corrupted ones. However Sometimes, instead of fixing everything, SFC finishes with this message:

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.

Found Corrupt Files but Was Unable to Fix Some of Them

This means SFC detected corrupted system files but could not repair all of them because the component store (which uses SFC as a source to repair files) is damaged. In this article, we’ll explain why this happens and suggest practical steps you can apply to fix the underlying problem in Windows 11 or Windows 10.

It usually means the Windows component store is damaged, and SFC can’t find a good source to restore from.

Contents

1 What Is System File Checker
2 Why SFC Cannot Fix All Corrupted System Files

What Is System File Checker

Let’s start with basics, System File Checker (SFC) is a built-in Windows command-line tool that scans for and repairs corrupted or missing critical Windows system files. When you run the sfc /scannow command, it scans protected Windows system files for any changes or corruption. Replaces incorrect, corrupted, or missing files with their proper versions from a local cache or Windows installation source.

In short:

System File Checker (sfc.exe) is a built‑in Windows tool.
It scans protected system files and compares them against known good versions stored in the Windows component store (WinSxS).
If it finds a bad or missing file, it tries to replace it with a cached copy from:
%WinDir%\System32\dllcache

On a healthy system, SFC often finishes with:

“Windows Resource Protection found corrupt files and successfully repaired them.”

If you get “found corrupt files but was unable to fix some of them”, SFC has reached its limits and needs help.

Why SFC Cannot Fix All Corrupted System Files

Sometimes SFC (System File Checker) can’t fix all corrupted files because its source, the local Windows Component Store (WinSXS), often becomes outdated or damaged itself. It means sfc tries to repair with bad data or the underlying corruption.

Common reasons include:

Deeper corruption in the Windows image (component store) that SFC depends on.
Pending operations or locked files that cannot be replaced while Windows is running.
File system errors or bad sectors on the disk.
Third‑party software, drivers, or security products are blocking changes.

The good news is that you still have several options:

Run SFC again in Safe Mode.
Use DISM /RestoreHealth to repair the Windows image.
Check the CBS.log to see what is failing.
As needed, use Startup Repair and other recovery tools.

Let’s walk through these fixes step by step.

Boot into Safe Mode and Run SFC Again

Sometimes third‑party services, drivers or startup programs interfere with SFC. Running SFC in Safe Mode often bypasses those conflicts.

Boot into Safe Mode (Windows 11/10)

Press Windows key + I to open Settings.
Go to System > Recovery (Windows 11) or Update & Security > Recovery (Windows 10).
Under Advanced startup, click Restart now.

After restart, go to: Troubleshoot > Advanced options > Startup Settings > Restart.

Press 4 for Safe Mode or 5 for Safe Mode with Networking.

Run SFC in Safe Mode

In Safe Mode, press Windows key + S, type cmd.
Right‑click Command Prompt and select Run as administrator.
In the elevated command window, run:
```
sfc /scannow
```
Wait for the scan to reach 100%.

Note the result.

Note: Make sure the PendingDeletes and PendingRenames folders exist under:
C:\Windows\WinSxS\Temp
If they are missing, SFC may not complete correctly.

If SFC now reports “successfully repaired them”, restart normally and check if your original problem is fixed.

If you still get “Windows Resource Protection found corrupt files but was unable to fix some of them”, move on to DISM.

Run DISM /RestoreHealth to Repair the Windows Image

If the component store (Windows image) is corrupted, SFC may not be able to get clean copies of system files. That’s when you need DISM.

DISM (Deployment Image Servicing and Management) can scan and repair the Windows image with:

DISM /Online /Cleanup-Image /RestoreHealth

Run DISM from an Elevated Command Prompt

Open Command Prompt as administrator (or Windows Terminal (Admin)).
Run: DISM /Online /Cleanup-Image /RestoreHealth

Wait patiently. This can take from 10–15 minutes up to an hour or more, depending on your system and corruption level.
DISM will check the component store, log corruption and attempt repairs using Windows Update by default.

When DISM finishes successfully, run SFC again:

sfc /scannow

In many cases, SFC can now repair previously unrecoverable files.

If DISM /Online /Cleanup-Image /RestoreHealth Fails

If DISM gives an error like 0x800f081f or 0x800f0906, Windows may not be able to download required files. In that case you may need to:

Check your internet connection.
Temporarily disable VPN/proxy/firewall.
Use a Windows installation ISO as a local source: right-click on iso file and select Mount.
```
DISM /Online /Cleanup-Image /RestoreHealth /Source:wim:D:\sources\install.wim:1 /LimitAccess
```
(Replace D: with the drive letter where the ISO is mounted.)

After DISM completes successfully, always run:

sfc /scannow

Then restart and test your system.

Use Startup Repair (Automatic Repair) When Windows Is Unstable

If the system is very unstable or will not start normally, you can try Startup Repair from the Advanced Startup environment.

Boot from a Windows 10/11 installation media or trigger Advanced Startup (Shift + Restart).

Go to Troubleshoot > Advanced options > Startup Repair.
Choose your Windows installation and let Startup Repair run.

Startup Repair attempts to fix:

Missing or corrupt system files needed for booting
Boot configuration problems
Some types of registry and disk metadata corruption

After Startup Repair completes, boot into Windows and try:

Running DISM /RestoreHealth.
Then running SFC /scannow again.

Check the CBS.log to See What SFC Could Not Fix

SFC logs its actions to CBS.log, which can help advanced users see exactly which files could not be repaired.

Locate CBS.log

Path:
C:\Windows\Logs\CBS\CBS.log

To open it:

Press Windows key + R, type:
```
C:\Windows\Logs\CBS
```
and press Enter.
Double‑click CBS.log.

If you see an Access denied error:

Right‑click CBS.log → Properties.
Go to Security tab → click Advanced.
Next to Owner, click Change.
Type Everyone, click Check Names, then OK.
Click Apply and OK.
Again, in Properties → Security, select Everyone and click Edit.
Check Full control, then Apply and OK.

Now you should be able to open CBS.log.

Search for “corrupt” entries

Open CBS.log in Notepad.
Press Ctrl + F, type corrupt, and click Find Next.

You’ll see lines indicating which files SFC found as corrupted and whether it could repair them.

In some special cases, you may:

Copy a clean version of a specific DLL or system file from another identical system or from installation media.
Re‑register a DLL if that’s all that is required.

However, manually replacing system files is advanced and risky. In most cases, using DISM + SFC is safer and easier.

Check the Disk for Errors with CHKDSK (Optional but Recommended)

Sometimes SFC fails because the disk itself has errors or bad sectors.

You can run CHKDSK to verify and fix disk/file system problems:

Open Command Prompt as administrator.
Run:
```
chkdsk C: /f /r
```
When asked if you want to schedule the scan at next restart, type Y and press Enter.

Restart the PC and let CHKDSK complete (this can take a long time on large or failing drives).

After CHKDSK finishes, try again:

DISM /Online /Cleanup-Image /RestoreHealth
Then sfc /scannow

For a full CHKDSK article, see: How to Use CHKDSK in Windows 11 and 10 to Fix Disk Errors.

When All Else Fails: System Restore or Reset This PC

If SFC and DISM still cannot repair all corrupted files and Windows remains unstable, you may need to consider more drastic options.

System Restore – Rolls back system files and settings to a previous restore point when your PC was working correctly.
Reset this PC – Reinstalls Windows 10/11 with an option to keep or remove your personal files.

Before using Reset this PC, always:

Back up your data (documents, pictures, etc.).
Note down installed programs and product keys.

Frequently Asked Questions

What does “Windows Resource Protection found corrupt files but was unable to fix some of them” mean?

It means the System File Checker found corrupted protected system files but could not repair all of them using its standard methods. You typically need to run DISM /RestoreHealth, then run SFC again, and possibly use Safe Mode or offline repair.

Is it safe to ignore this SFC error?

No. Ignoring unrepairable system file corruption can lead to:

More frequent crashes and blue screens
Windows Update failures
Features or apps not working properly

You should follow the steps in this guide to repair the underlying issue.

Will I lose my files when repairing SFC errors?

Tools like SFC, DISM and CHKDSK are designed to repair system files and the file system. They do not delete your personal files. However, when you use options like Reset this PC or perform a clean install, you may lose apps and settings (and personal files if you choose “Remove everything”). Always back up important data before major repairs.

Why does SFC keep finding corruption even after DISM?

If SFC and DISM repeatedly report corruption:

There may be a hardware issue (failing disk, bad RAM).
Malware or some third‑party software may still be modifying system files.
The Windows installation may be too badly damaged.

Check your disk and memory, scan for malware, and as a last resort, consider Reset this PC or a clean installation.

Should I run SFC in Safe Mode or normal mode?

You can run SFC in normal mode first. If it cannot complete or cannot fix files, try running SFC in Safe Mode as described above. Safe Mode loads fewer drivers and services, which often helps SFC complete without interference.