I recently upgraded by Windows 7 Home Premium machine to Windows 10 Home. The upgrade went fine and the machine's been running alright, except for one thing: I hibernate it every night when I'm done using it, and Win 7 stayed "off" until I turned it back on again whereas Win 10 seemingly randomly turns back on.
I've disabled Wake-on-LAN as well as wake on keyboard/mouse movement. Windows Update is configured to have me schedule the updates instead of installing them automatically. There doesn't seem to be anything relevant in the Event Viewer, although to be honest I'm not 100% sure what I'd be looking for there.
So what gives? How can I diagnose these random wake-ups and stop them?
I did read through this question and checked out my scheduled tasks and maintenance settings. There are four scheduled tasks and none are configured to wake up the system. The automatic maintenance is supposedly configured to run at midnight, but that doesn't seem to be the case. I came home today to find my machine running and the maintenance run date is reported as 4pm:
I also have the following in the Event Viewer:
The system has returned from a low power state. Sleep Time: 2015-09-23T03:47:52.760473200Z Wake Time: 2015-09-23T19:36:37.370293600Z Wake Source: Unknown
This 4 p.m. wake-up seems to be consistent with previous wake-ups. WindowsUpdate ran about 3 minutes after the machine reportedly "woke up", so I'm not sure if that's what woke it up or if it just started running since the machine wasn't in use. I did also see this question, which matches the behaviour I'm seeing, but unfortunately the "turn off automatic updates" solution doesn't apply since that's already off.
Is this a dead end? What else can I look at?