Does DISM need internet access?

/RestoreHealth uses Windows Update by default, so yes unless you supply a local /Source such as install.wim.

Should I run DISM or SFC first?

Run DISM first if you already know or suspect the component store is damaged; otherwise SFC alone is often enough for a first attempt.

How long does DISM /RestoreHealth take?

Usually 15-30 minutes, longer if it needs to download files over a slow connection.

Can DISM fix a PC that won't boot?

Yes, using /Image: instead of /Online while booted from recovery media, targeting the offline Windows partition.

What causes error 0x800f081f?

DISM can't reach a valid source for repair files. Supply install.wim from matching installation media with /Source and /LimitAccess.

Is ResetBase safe to run?

It's safe for disk space but removes the ability to uninstall previously installed updates, so only run it once the system is stable.

DISM (Deployment Image Servicing and Management)

DISM is a built-in Windows command-line tool for servicing the Windows image and component store — the repair source System File Checker depends on. This page covers DISM's own commands; for sfc /scannow itself, see the System File Checker guide.

Updated September 8, 2026 · PC Utility Hub Editorial Team

What DISM is for

DISM (Deployment Image Servicing and Management) manages Windows images, both online (the running OS) and offline (a mounted .wim or .vhd file). For everyday repair, its main job is checking and fixing the component store (WinSxS) — the source of clean files that System File Checker copies from when repairing individual files.

The three health commands

DISM /Online /Cleanup-Image /CheckHealth
DISM /Online /Cleanup-Image /ScanHealth
DISM /Online /Cleanup-Image /RestoreHealth

Command	What it does	Speed
/CheckHealth	Checks if corruption has already been flagged in the component store	Seconds
/ScanHealth	Actively scans the component store for corruption	10-15 min
/RestoreHealth	Scans and repairs the component store, downloading replacement files if needed	15-30 min

Using an ISO or install.wim/esd as the repair source

By default /RestoreHealth pulls repair files from Windows Update. If there's no internet access, or Update itself is broken, mount a Windows ISO and point DISM at the install.wim (or install.esd) inside its sources folder instead.

DISM /Online /Cleanup-Image /RestoreHealth /Source:WIM:D:\sources\install.wim:1 /LimitAccess
DISM /Get-WimInfo /WimFile:D:\sources\install.wim

The :1 selects the image index inside install.wim; run /Get-WimInfo first to list available indexes if unsure. For an install.esd source, convert the index reference the same way with :Index instead of :1 as needed.

Fixing error 0x800f081f

0x800f081f means DISM could not find the source files it needs — usually because Windows Update is unreachable or the local Group Policy is configured to block it as a source. Supply a local /Source pointing at install.wim from matching installation media, and add /LimitAccess to stop DISM from also trying Windows Update.

Component store cleanup: StartComponentCleanup and ResetBase

/StartComponentCleanup removes superseded versions of components that Windows Update no longer needs, similar to what Disk Cleanup's Windows Update Cleanup category does. Adding /ResetBase goes further: it removes all superseded versions permanently, which also frees more space but means you can no longer uninstall currently installed updates.

DISM /Online /Cleanup-Image /StartComponentCleanup
DISM /Online /Cleanup-Image /StartComponentCleanup /ResetBase

Warning: After /ResetBase, you can't roll back updates that were installed before running it. Only use it once you're confident the current update state is stable.

Offline repair with recovery media

When booted from Windows Recovery Environment, replace /Online with /Image:<drive>:\ pointing at the offline Windows partition, since the online-servicing flag doesn't apply to a system that isn't currently running.

DISM /Image:D:\ /Cleanup-Image /RestoreHealth /Source:WIM:E:\sources\install.wim:1

Correct order: DISM then SFC

Run DISM first when the component store itself is suspected of being damaged — for example, if SFC already reported it couldn't fix some files, or after a failed feature update. Once DISM confirms or repairs the component store, run sfc /scannow to fix any remaining individual file corruption; see the System File Checker guide for that command's full syntax and log analysis.

Get DISM

Start the download and follow the setup steps described on this page.

Frequently asked questions

Does DISM need internet access?: /RestoreHealth uses Windows Update by default, so yes unless you supply a local /Source such as install.wim.
Should I run DISM or SFC first?: Run DISM first if you already know or suspect the component store is damaged; otherwise SFC alone is often enough for a first attempt.
How long does DISM /RestoreHealth take?: Usually 15-30 minutes, longer if it needs to download files over a slow connection.
Can DISM fix a PC that won't boot?: Yes, using /Image: instead of /Online while booted from recovery media, targeting the offline Windows partition.
What causes error 0x800f081f?: DISM can't reach a valid source for repair files. Supply install.wim from matching installation media with /Source and /LimitAccess.
Is ResetBase safe to run?: It's safe for disk space but removes the ability to uninstall previously installed updates, so only run it once the system is stable.