Hi,
My name is Igor. It's a pleasure for me to help others and I'll try to help you. I am merely a fellow user trying to provide insight and information that may be helpful to others.
Please use Windows installation media and try recovery steps described at https://support.microsoft.com/en-us/help/4026030/how-to-use-windows-recovery-environment-winre-to-troubleshoot-common-s
Note, Step 7 may be faulty unfortunately.
If this will not help, use the same environment to run System Restore and roll back to the date before the problem appeared.
Please tell the result.