Windows

Energy management

Why computer was woken from sleep

To check why computer was woken from suspend:

powercfg /lastwake

To disable Windows Update waking up the computer

Run as Administrator:

gpedit.msc

Then go to:

Computer Configuration / Administrative Templates / Windows Components / Windows Update / Enabling Windows Update Power Management to automatically wake up the system to install scheduled updates

and set it to "Disabled".

For swedish Windows:

Datorkonfiguration / Administrativa mallar / Windows-komponenter / Windows Update / Aktivera automatisk väckning via Energisparfunktioner för installation av schemalagda uppdateringar

and set it to "Inaktiverad".