But for both of them when that happens, usually some problem third party program that windows can't shutdown properly. Such program may tip you off during use by telling you windows can't shut it down after you've used it, but you continue doing other things on computer. It can also be settings like Wake On LAN, Wake on Keyboard, Wake on Mouse, etc that interfere, but those are more rare. Obviously something hangs up the process and that's a software problem, not always easy to track down.
When I push a sleep mode button computer only shows the message "Preparing to hibernate" on blue screen all the time and doesn't go to sleep mode. I have to turn it off manually. Where is the problem? I never had such problem in the past. I need your advise, please.

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