And the computer has resumed going to sleep during periods in inactivity. The flashing windows were keeping it active. Thanks for the help.

The Malwarebytes solution appears to have worked. :)

I think once I fix the flashing window problem, the computer will go into sleep mode OK, I will try Malwarebytes. Thought there might be another solution, but anything is worth a shot.

I am having the exact same problem but it did not start (on Windows 10 Home) for me until the 1511 upgrade. It is quite irritating and I cannot find out what is causing it. It also then keeps the...