How to Use SFC /Scannow to Repair Windows System Files

Open Command Prompt as an administrator, very often referred to as an "elevated" Command Prompt.

Once Command Prompt is open, type the following command and then press Enter.

Write - sfc /scannow and press Enter.

System File Checker will now verify the integrity of every protected operating system file on your computer. It might take quite a while to finish.

Reboot Windows.