There are some base systems files that Windows must have to operate and to do so efficiently. For some time now there has been a utility to check these files and report on their well-being. This System File Check utility will check for damaged or corrupted files and repair what it can. You only need to run it from an elevated command prompt with the command “SFC /scannow”. The will initiate a complete of all the essential protected system files that would compromise your computer.
It, however, cannot always fix the problems on your system. Sometimes this due to Windows updates and sometimes it is due to other issues. When System File Checker cannot fix the system files there is a utility for Windows 8 and up called DISM. The utility will check the files not only with internal checksums but with checksums over the internet from Microsoft. There is a scan only option and a restore option. You can use the restore blindly without scanning but if you want to see if there is anything first you should use the /scanhealth option. You can run them back to back or use a single command line that will do if for you.
Back to Back would be:
DISM /Online /Cleanup-image /Scanhealth
DISM /Online /Cleanup-image /Restorehealth
Or both together:
DISM /Online /Cleanup-image /Scanhealth && DISM /Online /Cleanup-image /Restorehealth
(there is a space both before and after the &&)
DISM takes care of matching and fixing files based on what’s current on the Microsoft cloud but SFC is still the go to file checker. I would recommend running SFC then DISM then SFC once more to check that there are no more errors. Running SFC first will probably fix most of (if any) errors on your system but if it gives and error you then use DISM as a backup. Once finished with DISM you run SFC again to see if there are any unresolved errors left.
Both SFC and DISM can take some time to run depending on errors found and corrected. So, I would recommend doing them when you have down time that you wouldn’t need your computer.