If Windows 11 feels “broken” (updates failing, random errors, apps crashing, slow performance, or stability issues), the cause is often corrupted system files or a damaged Windows image. That’s exactly what SFC and DISM are designed to repair.
This guide explains what each tool does, when to use them, and the safest command order to fix Windows 11.
Start here (hub):
Windows 11 Troubleshooting Guide
Related fixes you may also need:
- If updates are stuck or failing: Fix Windows 11 update stuck
- If your PC is slow/fan loud: Windows 11 high CPU usage fixes
- If internet is unstable: Windows 11 Wi-Fi connected but no internet
What’s the Difference Between SFC and DISM?
SFC (System File Checker)
- Scans protected Windows system files
- Replaces corrupted files using the local Windows component store
DISM (Deployment Image Servicing and Management)
- Repairs the Windows image/component store that SFC relies on
- Especially useful when SFC can’t fix everything or keeps failing
Best practice: Run SFC first, then DISM, then SFC again (explained below).
When Should You Run DISM/SFC?
Run these tools if you notice:
- Windows Update keeps failing or errors appear repeatedly
- Random crashes, freezing, BSODs (after ruling out hardware)
- System apps misbehave (Settings, Microsoft Store, Start menu glitches)
- “Windows Resource Protection found corrupt files…” messages
- Performance issues caused by corruption (not normal “background activity”)
Before You Start (Important)
- Save your work and close apps
- Plug in your laptop (avoid power loss)
- Don’t shut down mid-scan unless Windows is completely frozen
Step 1: Run SFC (First Pass)
- Open Windows Terminal (Admin) or Command Prompt (Admin)
- Run:
sfc /scannow
What the results mean
- “Windows Resource Protection did not find any integrity violations.”
No corruption found. - “Windows Resource Protection found corrupt files and successfully repaired them.”
Reboot and test your issue again. - “Windows Resource Protection found corrupt files but was unable to fix some of them.”
Go to DISM (next step).
Step 2: Run DISM to Repair the Windows Image
Open Terminal/Command Prompt (Admin) and run:
DISM /Online /Cleanup-Image /RestoreHealth
Optional DISM checks (if you want more detail)
These are safe and sometimes faster for diagnosing:
DISM /Online /Cleanup-Image /CheckHealth
DISM /Online /Cleanup-Image /ScanHealth
- CheckHealth = quick check
- ScanHealth = deeper scan
- RestoreHealth = attempts repair
Let DISM finish. It can take 10–30 minutes depending on your PC.
Step 3: Run SFC Again (Final Fix)
After DISM completes, run SFC again:
sfc /scannow
Then restart your PC.
This second SFC run is important because DISM may repair the component store, allowing SFC to finally replace corrupted files.
If DISM Fails (Common Errors + Fixes)
1) DISM stuck at 62% / 84% / looks frozen
It can appear stuck but still be working.
- Wait at least 20–30 minutes
- Ensure your PC is not sleeping
- If it truly doesn’t move for a long time, reboot once and retry
2) DISM says “source files could not be found”
This usually happens when Windows can’t download repair files.
Try these:
- Make sure internet is working (see Wi-Fi guide if needed):Windows 11 Wi-Fi connected but no internet
- Temporarily disable VPN/proxy and retry
- Run Windows Update, then retry DISM
3) DISM fails because Windows Update components are broken
If updates keep failing, repair Windows Update first:
Fix Windows 11 update stuck
Then rerun DISM + SFC.
Advanced Option: Run SFC in Safe Mode (If Normal Mode Keeps Failing)
If Windows is unstable, run SFC in Safe Mode:
- Settings → System → Recovery → Advanced startup → Restart now
- Troubleshoot → Advanced options → Startup Settings → Restart
- Choose Safe Mode
- Run:
sfc /scannow
After Repair: What to Do Next
Once DISM/SFC completes:
- Reboot your PC
- Retry the exact thing that was failing (updates, app installs, settings opening, etc.)
- If your PC was slow, recheck Task Manager after reboot
If issues persist, it may be drivers/hardware or a deeper Windows problem.
FAQs (7)
- Should I run DISM or SFC first on Windows 11?
Run SFC first, then DISM /RestoreHealth, then SFC again for the best results. - How long do DISM and SFC take?
SFC: usually 5–20 minutes. DISM: 10–30 minutes (sometimes longer on slow disks). - Is it safe to close the window during the scan?
No. Let it finish. Interrupting can cause incomplete repairs. - Will DISM/SFC delete my files or apps?
No. These tools repair system components and protected files; they don’t remove personal data. - Why does SFC say it can’t fix some files?
Because the Windows image/component store is damaged—DISM repairs that store. - Do I need internet for DISM?
Often yes, because DISM may download repair files. If your internet is broken, fix connectivity first. - If DISM/SFC doesn’t fix it, what’s next?
Try driver updates, clean boot testing, or as a last resort an in-place repair/Reset (keep files).
