Run the sfc.exe /scannow command. -you can use system file checker (sfc.exe) to verify the integrity of protected system files. normally, windows xps windows file protection feature detects changes to protected system files and replaces damaged or deleted system files with a cached copy. however, this scenario illustrates an example of how changes to protected files can occur when the operating system is not running. therefore, windows file protection will not be triggered, and you will have to manually scan the system files using sfc.exe. use the /scannow switch to perform a scan immediately. the /scanboot switch configures the operating system to perform a scan every time the operating system boots. the /revert switch changes the scan behavior back to the default, and the /cachesize = size switch configures how much disk space can be used to store cached versions of protected system files.