sfc /scannow Explained: Repair Corrupted Windows Files (2026 Guide)

What is sfc /scannow? Repair corrupted Windows system files with one CMD command — full guide, what to do when it fails, and DISM combo. Windows 11/10.

CMD Commands Oct 15, 2026 0 8 Add to Reading List

sfc /scannow Explained: Repair Corrupted Windows Files (2026 Guide)

Windows acting weird — crashes, errors, broken features? Corrupted system files are often the hidden cause, and sfc /scannow is Microsoft's built-in repair tool that fixes them automatically.

This guide explains what the command does, how to run it correctly, what the results mean, and what to do when SFC alone can't fix everything (enter: DISM).

What Does sfc /scannow Do?
How to Run It Correctly
Understanding the Results
sfc /scannow Not Working? Fixes
The DISM Combo — When SFC Fails
When to Use SFC
Frequently Asked Questions
Conclusion

What Does sfc /scannow Do?

SFC = System File Checker. It scans every protected Windows system file, compares it to the cached original copy, and automatically replaces corrupted or missing files.

Fixes: crashes, missing DLLs, broken features, update errors
Cost: free, built-in, no downloads
Time: 5-15 minutes

Hindi: sfc /scannow Windows ke corrupt files ko khud dhoond ke repair karta hai — ek command, automatic fix.

How to Run It Correctly

Press Win + S → type cmd
Right-click Command Prompt → Run as administrator (required!)
Type:

```

sfc /scannow

```

Press Enter — let it complete (don't close the window)
Restart your PC after it finishes

⚠️ It must run as Administrator — normal CMD gives an error.

Understanding the Results

| Message | Meaning |

|---|---|

| "No integrity violations" | System files are clean ✅ |

| "Found corrupt files and repaired them" | Fixed — restart and test |

| "Found corrupt files but was unable to fix some" | Need DISM (below) |

| "Could not perform the operation" | Run in Safe Mode / check disk |

sfc /scannow Not Working? Fixes

"You must be an administrator" → reopen CMD as admin
Stuck at a percentage → let it finish; it's normal for it to pause
Won't run at all → run it in Safe Mode (Shift+Restart → Troubleshoot → Safe Mode)
Disk errors suspected → run chkdsk /f first, reboot, then SFC

The DISM Combo — When SFC Fails

If SFC can't fix files, repair the Windows image itself first:

```

DISM /Online /Cleanup-Image /RestoreHealth

```

Run DISM (as admin, needs internet)
Wait for it to finish (10-20 min)
Then run sfc /scannow again — it now has healthy source files to repair from

Order matters: DISM first, then SFC.

When to Use SFC

After a crash/power-cut corrupted something
Windows features randomly broken (Start menu, Settings)
Windows Update errors
Before reinstalling — worth a try first
Monthly maintenance on problem PCs

Frequently Asked Questions

What does sfc /scannow actually do?

It scans all protected Windows system files and replaces corrupted or missing ones with healthy cached copies — Microsoft's built-in repair tool.

How long does sfc /scannow take?

Usually 5-15 minutes. It can pause at percentages — that's normal; don't close it.

Is it safe to run sfc /scannow?

Yes — it only repairs Microsoft system files and doesn't touch your personal data, apps, or files.

What if sfc /scannow finds errors it can't fix?

Run DISM /Online /Cleanup-Image /RestoreHealth first, then run sfc again — DISM repairs the source image SFC uses.

Do I need to run sfc /scannow regularly?

Not required on a healthy PC — run it when things break: crashes, update failures, or broken Windows features.

sfc /scannow kaise chalaye?

CMD as Administrator kholo → sfc /scannow type karo → Enter → 5-15 min wait → restart PC.

Conclusion

sfc /scannow is the first command to reach for when Windows misbehaves — admin CMD → scan → restart. If it can't fix everything, DISM repairs the image, then SFC finishes the job.

???? Video Tutorial: [Embed YouTube video — CMD Commands #06]