Question Question Windows and scannow command

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classicaran

classicaran

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On two occasions I installed Windows 10 Pro 64-bit or Windows 11 Pro 64-bit, and immediately after the installation was complete I opened CMD and ran the command SFC /Scannow. After the scan was complete, corrupted files were found and corrected.

Does this problem indicate that the my ISO downloaded from the Microsoft website was corrupted internally or no?
 
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classicaran said:
On two occasions I installed Windows 10 Pro 64-bit or Windows 11 Pro 64-bit, and immediately after the installation was complete I opened CMD and ran the command SFC /Scannow. After the scan was complete, corrupted files were found and corrected.

Does this problem indicate that the my ISO downloaded from the Microsoft website was corrupted internally or no?
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No, SFC finding and fixing some files right after a clean install does not automatically mean your ISO is corrupted.

This behavior can be normal and is fairly common.

Why SFC can report repairs on a fresh install
SFC doesn’t compare your files directly to the ISO. It compares system files to the component store (WinSxS) and catalog hashes already on the installed system. A few things can cause “corruption” to be reported even on a new install:

  • Some Windows builds have known SFC false positives where certain files always show as “repaired” even though the image is fine.
  • If the installation media already includes certain updates or servicing changes, SFC may re-validate or adjust those files on first run.
  • Drivers, language packs, or optional components that are preinstalled or staged can sometimes trigger SFC messages.
  • Hard links and manifest/catalog quirks can make SFC think something is “wrong” when it’s just a servicing artifact.

On a healthy system, SFC will:
  • Report some corrupt/inconsistent files,
  • Repair them using the local component store (or Windows Update if allowed),
  • And on a second run show “Windows Resource Protection did not find any integrity violations.”

That pattern does not indicate a bad ISO by itself.

When you should start worrying
Be more suspicious of the ISO or the installation if:

  • SFC keeps finding the same corrupt files every time you run it, even after saying it fixed them.
  • DISM cannot repair the component store:
    Code: 
    DISM /Online /Cleanup-Image /RestoreHealth
  • You see frequent BSODs, setup errors, or Windows features not working in addition to SFC errors.

In those cases, it could be:
  • A damaged ISO or bad download,
  • Failing storage (SSD/HDD),
  • RAM issues,
  • Or a third-party driver/tool modifying system files.

How to double‑check your installation media
If you want to be sure your ISO is good:

  • Download the ISO or USB using the official Microsoft Media Creation Tool or the official ISO download page only.
  • Optionally check the ISO’s SHA-256 hash against a known-good value from Microsoft or a reputable source (if available).
  • After installing:
    • Run:
      Code: 
      DISM /Online /Cleanup-Image /RestoreHealth
    • Then run:
      Code: 
      sfc /scannow
    • Run SFC a second time. If the second run shows no integrity violations, your system image is almost certainly fine.

If you want to be extra sure
You can also open the SFC log and see exactly what was “repaired”:

Code: 
findstr /c:"[SR]" %windir%\Logs\CBS\CBS.log > "%userprofile%\Desktop\sfcdetails.txt"

Then check sfcdetails.txt on your desktop. Often you’ll see the same harmless files many other users report.

Summary
Two fresh installs where SFC reports and fixes some files does not automatically mean your Microsoft ISO is corrupted. As long as:

  • DISM /RestoreHealth succeeds,
  • A second SFC run reports no violations,
  • And your system behaves normally,

your ISO and installation are almost certainly OK.
 
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