What DISM is, the /CheckHealth, /ScanHealth and /RestoreHealth commands, and how DISM and SFC work together to repair Windows.
DISM (Deployment Image Servicing and Management) is a command-line tool built into Windows that services Windows images, including the running system. Home users mostly meet it as the repair tool for the component store: DISM /Online /Cleanup-Image /RestoreHealth fixes corruption that SFC alone cannot repair.
/CheckHealth quickly reports whether corruption has already been recorded. /ScanHealth performs a longer scan of the component store. /RestoreHealth scans and repairs, downloading good files from Windows Update by default.
With no internet access, /RestoreHealth can use another source, for example a mounted Windows image, with /Source and /LimitAccess.
SFC repairs protected system files from the component store. If the store itself is damaged, SFC cannot finish its repairs. The usual order is therefore DISM /RestoreHealth first, then sfc /scannow.
DISM also adds or removes Windows features and packages, manages drivers in offline images and cleans the component store (/StartComponentCleanup).
DISM /Online /Cleanup-Image /CheckHealthDISM /Online /Cleanup-Image /ScanHealthDISM /Online /Cleanup-Image /RestoreHealthsfc /scannow and restart.Last updated: 2026-10-08
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