The first thing to check: One of the ‘usual culprits’ that has traditionally prevented my PCs from sleeping over the years has been ‘when sharing media, prevent idling to sleep’ power setting. It should be sleeping after the pre-configured time of PC inactivity. However, lately I walk into my study after hours of inactivity and see the PC still powered on. My basic power settings show a ‘balanced’ power plan, with the following settings: My Windows 10 desktop used to go to sleep as expected.