Windows 10 start menu/Cortana broken after Norton install

I have been having trouble with my Windows 10 start menu and Cortana no longer working so I reinstalled Windows yesterday.  Up until I restarted to complete the Norton installation, they were working.  As soon as I restarted they are no longer working again.  I had not made this connection before for certain but it seems pretty clear now. Everything works fine in safe mode.

Is there anything known about this as relates to Norton?

Thanks.