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DISM and SFC repair different layers of Windows. DISM repairs the Windows component store, which provides replacement files. SFC then checks protected system files and replaces damaged copies using that repaired store.
For a working installation, run DISM first and SFC second. If Windows will not boot, run their offline forms from Windows Recovery Environment (WinRE). The commands below cover Windows 10 and Windows 11, including repairs that need a matching ISO, USB drive, or network source.
Before you start
- Save open work and connect the PC to AC power.
- If Windows still starts, install pending updates and restart once.
- Back up important files if the system is unstable or the disk may be failing.
- Check the installed version with
winver. This matters when you need installation media as a repair source.
Open an elevated Command Prompt:
- Select Start and type
cmd. - Right-click Command Prompt and choose Run as administrator.
- Approve the User Account Control prompt.
You can also confirm the installed edition with:
dism /online /Get-CurrentEditionIn DISM, /Online means “the Windows installation currently running.” It does not mean that DISM automatically uses the internet, although Windows Update may be used as a repair source.
Standard online repair: DISM, then SFC
Use these commands when you can sign in to Windows normally or in Safe Mode. Run each command in the elevated Command Prompt and wait for it to finish before entering the next one.
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1. Check the component store
A quick check shows whether Windows has already marked the component store as corrupted:
DISM.exe /Online /Cleanup-Image /CheckHealthFor a more thorough scan, use:
DISM.exe /Online /Cleanup-Image /ScanHealth/CheckHealth is relatively quick. /ScanHealth examines the store for corruption and can take several minutes. Neither command repairs anything.
2. Repair Windows with DISM
DISM.exe /Online /Cleanup-Image /RestoreHealthFor an online image, DISM normally obtains missing repair files through Windows Update. Keep the PC connected to the internet unless you are supplying a local source. A progress percentage can remain unchanged for quite a while; do not close the window just because it appears stuck.
Wait for a message similar to:
The restore operation completed successfully.3. Run System File Checker
After DISM completes successfully, run:
sfc /scannowLeave the Command Prompt open until verification reaches 100%. Restart Windows when SFC finishes, even if it repaired only a small number of files.
What SFC’s result means
| Result | Meaning | Next step |
|---|---|---|
| Windows Resource Protection did not find any integrity violations. | SFC found no corruption in protected system files. | Restart and test the original problem. |
| Windows Resource Protection found corrupt files and successfully repaired them. | SFC replaced the damaged files. | Restart Windows and check whether the problem is resolved. |
| Windows Resource Protection found corrupt files but was unable to fix some of them. | Some files could not be replaced. | Review the SFC details and confirm that DISM completed successfully. If necessary, use a matching local source or offline repair. |
| Windows Resource Protection could not perform the requested operation. | SFC could not complete its scan. | Try Safe Mode, or run SFC offline from WinRE. |
To extract SFC entries from the CBS log on a running installation, use:
findstr /c:"[SR]" %windir%LogsCBSCBS.log >"%userprofile%Desktopsfcdetails.txt"The CBS log can contain results from several scans. Check timestamps before deciding that an entry belongs to the latest run.
Repair DISM with a local Windows source
Use a local source when DISM returns 0x800f081f: The source files could not be found, Windows Update is unavailable, the PC has no internet connection, or company policy blocks access to Windows Update.
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A directory containing known-good Windows files can be specified like this:
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DISM.exe /Online /Cleanup-Image /RestoreHealth /Source:C:RepairSourceWindows /LimitAccessReplace C:RepairSourceWindows with the actual path. /LimitAccess stops DISM from contacting Windows Update, so use it only when the local source is complete and appropriate.
A network source is also possible:
DISM.exe /Online /Cleanup-Image /RestoreHealth /Source:\ServerNamec$Windows /LimitAccessThe source computer should use the same Windows generation and a closely matching feature-update version as the target. A Windows 10 source is not a suitable substitute for Windows 11, and an old feature-update image may not contain the components required by a newer installation.
Match the repair source carefully
For reliable results, match the target installation’s:
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- Architecture: x64 or ARM64
- Edition: Home, Pro, Enterprise, or Education
- Language and servicing state, as closely as practical
A monthly cumulative-update difference does not necessarily make a source unusable, but a different feature-update version, architecture, edition, or language can cause source-not-found or applicability errors. As of October 14, 2025, ordinary Windows 10 22H2 editions have reached the end of standard support; LTSC editions follow separate lifecycles. Use supported Windows 11 media where appropriate, and match the target version rather than choosing media solely because it says “Windows 11.”
Use an ISO or USB containing install.wim or install.esd
Mount a Windows ISO by double-clicking it, or connect the installation USB. Assume the media is drive X:. First inspect the image file instead of guessing its edition index.
For a WIM file:
DISM /Get-WimInfo /WimFile:X:sourcesinstall.wimFor an ESD file:
DISM /Get-WimInfo /WimFile:X:sourcesinstall.esdRecord the index that corresponds to the installed edition. Then use the matching command, replacing INDEX:
DISM /Online /Cleanup-Image /RestoreHealth /Source:WIM:X:sourcesinstall.wim:INDEX /LimitAccessDISM /Online /Cleanup-Image /RestoreHealth /Source:ESD:X:sourcesinstall.esd:INDEX /LimitAccessIf DISM rejects the direct WIM or ESD path, mount the correct image index and use its Windows directory as the source:
mkdir C:MountDISM /Mount-Wim /WimFile:X:sourcesinstall.wim /Index:INDEX /MountDir:C:Mount /ReadOnlyDISM /Online /Cleanup-Image /RestoreHealth /Source:C:MountWindows /LimitAccessWhen the repair is complete, remove the temporary mount:
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DISM /Unmount-Wim /MountDir:C:Mount /DiscardDo not use a random index. A multi-edition ISO can contain several images, and selecting the wrong one is a common reason for error 0x800f081f.
Offline repair when Windows will not boot
Enter Windows Recovery Environment
From Windows 11, go to Settings > System > Recovery > Advanced startup > Restart now.
From Windows 10, go to Settings > Update & Security > Recovery > Advanced startup > Restart now.
You can also hold Shift while selecting Power > Restart. If Windows cannot reach the desktop, boot from Windows installation media, select the language and keyboard options, choose Next, and then select Repair my PC.
In WinRE, select:
Troubleshoot > Advanced options > Command PromptIf BitLocker is enabled, WinRE may request the BitLocker recovery key.
Find the correct drive letters
WinRE often assigns different letters than normal Windows. The installed system may be D: or E:, not C:.
diskpartlist volumeexitTest likely volumes:
dir C:Windowsdir D:Windowsdir E:WindowsUse the volume containing the real Windows directory. Identify the installation-media letter by looking for setup.exe and a sources folder. The examples below assume Windows is on D: and the media is on E:.
Run offline DISM
Scan the offline installation:
DISM /Image:D: /Cleanup-Image /ScanHealthRepair it using Windows Update-equivalent servicing files already available to the recovery environment or image:
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DISM /Image:D: /Cleanup-Image /RestoreHealthTo use a WIM or ESD on installation media, first identify its index with the appropriate /Get-WimInfo command, then run:
DISM /Image:D: /Cleanup-Image /RestoreHealth /Source:E:sourcesinstall.wim:INDEX /LimitAccessDISM /Image:D: /Cleanup-Image /RestoreHealth /Source:E:sourcesinstall.esd:INDEX /LimitAccessIf the direct source is not accepted, mount the image:
mkdir D:MountDISM /Mount-Wim /WimFile:E:sourcesinstall.wim /Index:INDEX /MountDir:D:Mount /ReadOnlyDISM /Image:D: /Cleanup-Image /RestoreHealth /Source:D:MountWindows /LimitAccessDISM /Unmount-Wim /MountDir:D:Mount /DiscardRun offline SFC
After offline DISM completes, scan the offline Windows installation:
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sfc /scannow /offbootdir:D: /offwindir:D:Windows/offwindir identifies the offline Windows directory. /offbootdir identifies the boot directory. On some systems the boot files are on a separate, small system partition, so do not assume both paths use the same letter. Confirm the layout in DiskPart if the command fails.
For a targeted file scan, use:
sfc /scanfile:D:WindowsSystem32kernel32.dll /offbootdir:D: /offwindir:D:WindowsRestart from WinRE with:
wpeutil rebootCommon errors and what to do
DISM Error 87
Error 87 generally means invalid syntax. Check for a misspelled option, a missing space, or smart punctuation copied from a formatted webpage. Use ordinary hyphens, forward slashes, colons, and straight quotation marks.
A valid online command is:
DISM.exe /Online /Cleanup-Image /RestoreHealthDISM Error 0x800f081f
“The source files could not be found” usually indicates one of these problems:
- Windows Update cannot provide the required files.
- The ISO or network source is for the wrong feature-update version.
- The wrong WIM or ESD index was selected.
- The source path is incorrect.
/LimitAccesswas used with an incomplete or incompatible source.
Verify the image index, check the drive letter, and use media matching the target’s edition, architecture, language, and Windows generation.
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Try SFC in Safe Mode. If it still fails, run the offline command from WinRE and verify both drive letters. Microsoft also recommends checking that these directories exist on the running installation:
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%WinDir%WinSxSTempPendingDeletes%WinDir%WinSxSTempPendingRenamesDISM and SFC finish, but Windows is still broken
These tools repair the component store and protected system files. They do not fix every startup or stability problem. Persistent failures can be caused by bad storage, defective RAM, malware, incompatible drivers, damaged boot configuration, registry problems, or third-party software.
For a boot failure, try Troubleshoot > Advanced options > Startup Repair. Startup Repair targets several startup-related problems, including damaged system files, boot-configuration data, incompatible drivers, and certain registry errors.
When to use a reinstall instead
Stop repeating DISM and SFC when the component store is reported as non-repairable, the same commands repeatedly fail with a matching source, or Windows remains unstable after successful repairs.
Do these 3 things before closing this tab:
1Repair Windows errors before they cause bigger problems2Scan for outdated or missing drivers - takes under a minute3Clear out junk files and repair common Windows errors- Back up personal files.
- Check the health of the storage drive and test memory.
- Review
C:WindowsLogsDISMdism.logandC:WindowsLogsCBSCBS.log. - Try System Restore, Startup Repair, or Reset this PC from Windows Recovery.
- On Windows 11, check Settings > System > Recovery > Fix problems using Windows Update > Reinstall now. When available, this reinstalls the current version while preserving apps, files, and settings.
- For an in-place reinstall, start
setup.exefrom installation media while signed in to Windows. Select Change what to keep > Keep personal files and apps.
Be careful when booting directly from installation media: choosing a fresh installation is not the same as an in-place repair and can remove apps, files, or partitions depending on the choices made.
DISM and SFC advice to avoid
- Do not run SFC first by default. The current Microsoft procedure is DISM first, then SFC.
- Do not run SFC three times just because a guide says so. There is no fixed number of required repetitions. Read the result and address the repair-source problem.
- Do not interpret
/Onlineas “download from the internet.” It identifies the currently running target image. - Do not assume WinRE uses
C:. Verify the Windows volume. - Do not guess the ISO index. Use
/Get-WimInfofirst.
FAQ
Should I run DISM or SFC first?
Run DISM.exe /Online /Cleanup-Image /RestoreHealth first, then run sfc /scannow. DISM repairs the component store that SFC uses as a source for protected system files.
Can DISM repair Windows without internet access?
Yes. Supply a matching local directory, ISO, USB, or network share with /Source and use /LimitAccess to prevent DISM from contacting Windows Update. The source must closely match the target Windows version, edition, architecture, and language.
Why does DISM say the source files could not be found?
Error 0x800f081f commonly results from a wrong WIM/ESD index, incorrect drive letter or path, unavailable Windows Update files, or media from a different feature-update version. Use DISM /Get-WimInfo to identify the correct edition index.
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They can repair some system-file and component-store causes, but not every boot problem. Run their offline forms from WinRE after confirming the Windows drive letter. Also try Startup Repair when the failure involves boot configuration, drivers, or other startup components.
The Bottom Line
For a running PC, use DISM.exe /Online /Cleanup-Image /RestoreHealth, wait for it to finish, and then run sfc /scannow. For an unbootable PC, identify the Windows volume in WinRE and use /Image with offline SFC parameters. If a source is required, match the ISO or WIM/ESD index to the installed Windows version instead of repeatedly retrying the same command.
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