Fix Corrupted Windows System Files with DISM

If your PC is suddenly crashing, throwing random update errors, or acting sluggish, you are likely dealing with corrupted system files. Instead of reinstalling Windows, you can use a built-in tool called DISM to scan your system and automatically repair those damaged components.

Why this happens

System file corruption usually occurs due to an interrupted Windows update, an unexpected power loss, or a dying storage drive. DISM reaches out to the Windows update servers to replace your broken files with fresh, healthy copies.

What you'll need

You will need administrative access to your computer and an active internet connection, as the tool needs to pull clean files directly from Microsoft servers.

Steps

1. 01
   Open the Start menu, type CMD, right-click on 'Command Prompt', and select 'Run as administrator' to ensure you have the permissions required to modify system files.
2. 02
   In the black window that appears, type DISM /Online /Cleanup-Image /RestoreHealth and press Enter.
3. 03
   Wait for the progress bar to reach 100 percent, which can take anywhere from 5 to 20 minutes depending on your disk speed.
4. 04
   Once you see the message 'The restore operation completed successfully', restart your computer to finalize the repairs.

Still not working?

If DISM finishes but you are still experiencing system instability, your core Windows image might be deeply damaged. Run the System File Checker by typing sfc /scannow in an elevated Command Prompt. If errors persist after both tools, check your drive health using tools like CrystalDiskInfo, as file corruption is often an early symptom of a failing hard drive or SSD.

Frequently asked questions

Will running this command delete my personal files?

No, this process only scans and repairs Windows system files. Your photos, documents, and installed programs remain untouched.

How often should I run this?

You do not need to run this regularly. Use it only when you experience persistent errors, crashes, or after a major Windows Update fails to install.

What does the 'Online' part of the command mean?

It means the tool is performing the repair while your operating system is running. It uses your internet connection to fetch the correct, healthy versions of corrupted files from Microsoft.