Windows File Protection

Windows 10 and earlier versions of Windows include Windows File Protection, which helps to prevent the corruption of system files. When protected files change directories, Windows File Protection (working in the background) will check the file against a file signature catalog. A cache of backup files is kept at C:\Windows\System32\dllcache. Bad system files will be replaced.

If you run the command:

sfc /scannow

. . . in the System32 folder, the utility System File Checker will perform a comprehensive search for any corrupted system files and replace any it finds with the backups stored in the cache folder.