After Windows Updates, PC Doesn't Turn Back On

[yilmoo]

Whenever I allow the computer to complete a pending Windows Update, the power button no longer works to turn the PC back on.

Example: Last night I had a pending windows update. When finished using the computer I selected "Update & Shut Down" when turning off to allow the update. The next morning the Power Button does not work to turn the computer back on.

This has happened a few times now. The fix that works requires me to disconnect the PC from power, and then re-connect it to power. After doing so, the Power button works, the PC turns on and functions normally. 

Why is this happening? It's annoying and I'm worried it could be indicative of a worse problem? Thanks. 

[WAWood]

@yilmoo 

Win10 has enabled a new hibernation process known as Fast Startup -- which is enabled BY DEFAULT. This is different from Fast Boot, which is a BIOS/UEFI option.

Fast Startup is supposed to dramatically speed up the booting process, but in some PCs, it actually slows it down or causes it to hang. It's also a new form of hibernation known as hybrid sleep -- and this causes battery drain to maintain the state of the PC while turned off. In some rare cases, it can also cause a laptop to overheat because the processor is still running and still generating heat, as this has been reported when the laptop was turned off and put inside a case.

Disabling Fast Startup might fix booting and shutdown problems.

There are two ways to disable FastStartup in Win10: (1) through the Control Panel, and (2) through an elevated command prompt.

Control Panel - Open Control Panel --> Power Options.
Select "Choose what the power buttons do"
Select "Change settings that are currently unavailable"
At the bottom of the Window, under Shutdown settings, uncheck the box regarding fast startup

Elevated command prompt - run the following command:
REG ADD "HKLM\SYSTEM\CurrentControlSet\Control\Session Manager\Power" /V HiberbootEnabled /T REG_dWORD /D 0 /F

In both cases, reboot Windows.

NOW, Fast Startup is disabled.

See if that helps.