Sign in as the Administrator on your computer. If you do not see the administrator account, enable the administrator account. If you are using a home version, you will need to go to an elevated command prompt and type the following –
net user administrator /active:yes
After logging in as the administrator, type the following at an elevated command prompt-
Dism /Online /Cleanup-Image /RestoreHealth
Note: Your computer may appear to hang – wait, it will take time
Reboot after running the DISM command.