Power light on but no boot

A quick google came up with the following for this issue - it was used for win7, I just had a look in Win10 and the instructions remain the same:-

1. Go back in to Safe Mode
2. Type msconfig. (This will bring up the System Configuration window.)

3. Go to the Boot tab.
4. If selected, remove the tic from Safe boot.
5. Click Apply and then OK.
6. Restart your computer.

I went into System Restore and saw there had been a Critical Update immediately before all my troubles started. I have reset to an earlier restore point and will see what happens.

Thanks, damocels -- I will do that.