Windows Resource Protection

The message “Windows Resource Protection could not start the repair service” appears when running sfc /scannow and the underlying Windows Resource Protection (WRP) infrastructure cannot start its required service (Windows Modules Installer/TrustedInstaller).

WRP is the mechanism that protects and repairs essential system files, folders, and registry keys. It only allows changes through the Windows Modules Installer service using supported replacement mechanisms. When sfc /scannow runs, it relies on this infrastructure to scan and repair protected files. If the repair service cannot start, SFC cannot complete and shows that error.

To address this situation, use the System File Checker as documented and pay attention to the result messages:

1. Open an elevated Command Prompt (Run as administrator).
2. Run:

      sfc /scannow
   

3. If the scan cannot run and shows “Windows Resource Protection could not perform the requested operation,” run SFC in Safe Mode and verify that the folders PendingDeletes and PendingRenames exist under %WinDir%\WinSxS\Temp.
4. If SFC completes, interpret the result:
   • If it reports that corrupt files were found and successfully repaired, no further action is needed beyond reviewing the CBS log if desired.
   • If it reports that corrupt files were found but some could not be fixed, identify the specific files from the CBS log and replace them manually with known-good copies.

Because WRP strictly controls access to protected resources, applications and installers must not attempt to modify WRP-protected files or registry keys directly. All repairs must go through SFC/WRP and the Windows Modules Installer service.

References:

• Use the System File Checker tool to repair missing or corrupted system files
• About Windows Resource Protection