Home / Guides / Command Prompt Fixes

DISM /RestoreHealth: Repairing Windows System Files

Intermediate Command Prompt Fixes Applies to: Windows 10, Windows 11

When sfc /scannow can't fix what it finds, DISM repairs the underlying system image it relies on.

Before you start: save any open work and note down what you were doing when the problem started — that context helps if you need to search further or ask for help.
  1. Open Command Prompt as administrator, then type DISM /Online /Cleanup-Image /RestoreHealth and press Enter.
  2. Let it run fully — it can take 10-30 minutes and will appear to pause at certain percentages (commonly 20% and 40%); this is normal, not a freeze.
  3. DISM needs an internet connection by default, since it downloads replacement files directly from Windows Update to repair the local image.
  4. Once it completes successfully, run sfc /scannow again — DISM repairs the reference image, and sfc uses that repaired image to fix your actual system files.
  5. If DISM itself fails with an error, note the specific error code and search for it — common causes include a corrupted Windows Update cache or a metered network connection blocking the download.
Still not fixed? Send us the details and we'll help you dig further, or browse related guides in Command Prompt Fixes.

Frequently Asked Questions

Do I need an internet connection for DISM to work?
Usually yes — by default DISM downloads replacement files from Windows Update to repair the image. Without internet access, you'd need a Windows installation source specified manually instead.
How is this different from sfc /scannow?
sfc checks and repairs individual system files using a local reference, while DISM repairs the underlying Windows image those references come from — running DISM first, then sfc, is the correct order when both are needed.

Related guides

Command Prompt Won't Open

Typing "cmd" into the Start menu does nothing, or Command Prompt flashes open and immediately closes.

Beginner

How to Run Command Prompt as Administrator (and Why It Matters)

Many repair commands fail silently or refuse to run unless Command Prompt has administrator privileges.

Beginner

sfc /scannow Explained: What It Does and How to Read the Results

The most common Windows repair command — here's what it actually checks and what its output means.

Beginner