System won't wake after being idle for 10 to 15 minutes

[Mamitha]

After laptop being idle for 10 to 15 minutes system won't wake up with any keyboard or mouse movement. It will wake only if I restart the system

I tried going to the device manager to allow it. However there is no power management tab and change setting is greyed out. 

I tried connecting external mouse and checked for the same. Power management tab was available,However even after checking the allow  still I was not able to wake the system

[WAWood]

@Mamitha 

If it is a laptop running Windows 10 and you had it turned off, it was not idle -- regardless of what you think.

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.

[Mamitha]

@wawood

Thanks for the reply

However it didn't solve the issue.

Since I was not able to find the fast startup option in control panel So  I did it through command prompt and restarted the system

I locked the screen then tried waking it after 20 to 25minutes I was not able to do it. I had to restart the system.

[WAWood]

@Mamitha 

Sorry that did not work -- as I don't have anything else to suggest.