Hi
I came back to say that I finally found a solution.
I had tried many solutions that people suggested, it seems I'm not the only person to have this problem. None of them worked for me.
I found many people complaining until I found this answer.
Open Task Manager.
Click on File.
Select Run New Task.
Type in Powershell.
Click the box that says Create Task with Administrator Privileges.
Click OK
That opened the Powershell with Admin privileges.
I was able to run SFC /scannow and it worked found errors and fixed them.
The answer was simple, my links on the Start Menu still don't work but the Admin Powershell does.
I still don't know why the normal method doesn't work but at least I have a simple workaround.
Mike