Thanks @wmdavid.wallace ! I had this exact problem and it was driving me nuts. Your solution solved it.I keep my PC right up to date most of the time. Recently I found that my PC would not remain asleep if I clicked on the sleep option however if I set my mouse on a nearby shelf and briefly used the power button (which on this system is set to sleep) then all was well. As best I can tell the slightest mouse activity wakes the machine. I tried setting my PC not to wake on mouse activity ( thru Device Manager as best I recall ) but that did not help. My mouse and keyboard are wireless Logitech devices. Not sure if this is the same issue you are seeing or not.