Friday’s daily OS Update had me offline for 3 days, unfortunately I’m unable to say exactly what it was that I did to fix it.
However today, I discovered that on boot, the system is not booting from the boot drive.
So, when booting I use the F8 key to display all drives and select the correct drive.
Friday’s and today’s OS Updates seem to have messed with boot file.
After going through this non-sense several times the booting eventually returns to normal.