Ran DISM /Online /Cleanup-Image /RestoreHealth in an admin command prompt because sfc found corrupt files. It sits at 62% for ages then says source files could not be found. Windows 10. What's the usual fix?
If it's just sitting on one percentage, give it time. It's known for parking at around 20% or 62% for a long while and then finishing. I'd leave it at least half an hour before killing it.
If it fails with "source files could not be found" (0x800f081f), it can't get clean files from Windows Update, so give it a source. Download a Windows ISO of the same version and edition, double-click it to mount it, note the drive letter, then run:
DISM /Online /Cleanup-Image /RestoreHealth /Source:wim:D:\sources\install.wim:1 /LimitAccess
Change D: to your drive letter. Some ISOs have install.esd instead of install.wim, use esd: in that case. The :1 is the edition index, and dism /get-wiminfo /wimfile:D:\sources\install.wim lists them if 1 isn't yours.
After that succeeds, run sfc /scannow. If DISM still fails with a proper source, run setup.exe from the same ISO and choose to keep files and apps. That in-place repair replaces the system files without wiping anything.
