I have a new HP Windows 8 computer (just got it on Christmas) and just last night it started not shutting down. It will go to the point of a black screen (after it says 'shutting down') but all the lights on the keyboard and the power button will stay on. I've tried disabling the fast start up thing, but that didn't work. This behaviour only started last night, and it was left on because I was unaware of the problem. I've been having to resort to pressing and holding the power button because I haven't got a clue what to do. Please help!
Well this is a recent situation and have seen many cases, in which the actual issue was with hardware !! So the best solution is to bring back to the place of purchase and have it replaced or repaired under the warranty.
However, before claiming warranty, lets give it a go with one possible cause i.e.
usb sockets not powering up properly from suspend when a system shutdown command is initiated. Disable the USB selective suspended setting and check if it solves the issue. HEre is how to do it...
Open your Power Options
then Click on Change Plan Setting
on the next screen, click on Change advanced power settings
A new power options window will open, in which scroll down to USB Settings and Expand it by clicking the Plus sign... now expand, USB selective suspended setting and in the options, select Disabled for both on battery and plugged in....
restart your PC and shut down to check if it completely shutdowns or not !!
start cmd.exe as a admin
run powercfg.exe /energy
copy the report from its default location and take a look. sometimes it will point out a service that is blocking a sleep or shutdown request.
also look in event viewer for errors, there are some programs that refuse to shutdown when requested by the operating system and windows will attempt to kill them but can not in certain cases. (program stuck attempting to write to data to hard drive, killing program might result in data loss)
basically, the OS tells the program to shutdown, the program says no because it is waiting for a write to the hard drive to complete, because of issues the program never gets it write completion notification and never allows the program to exit. often caused by using lazy writes on a disk or network drive or a network drive that is configured for lazy writes on its own drive subsystem.