I have a similar problem. My PC comes out of sleep or hibernation around or just after midnight. My network adapters are not allowed to wake the computer and my Power Options Advanced settings has Sleep Allow wake timers set to Disable. Going to Control Panel > System and Security > Administrative Tools > Schedule tasks I get to the Task Scheduler. At the bottom of the page are found Active Tasks. There I find 'Maintenance Configurator' with Next Run time to be at 1:00 AM, and 'BackgroundConfigSurveyor' with Next Run time to be at 3:00 AM. I suspect these and perhaps more are the culprits. I cannot change the times as when I try to edit them I get back "Task Scheduler service is not available. Task Scheduler will attempt to reconnect to it.' which seems to mean even though I am the administrator I lack the authority to do so. Under Windows 7 SP1 with the same adapter and power settings Sleep and Hibernation work fine. Under Windows 8.1 I have to shut down the PC to stop it from waking up in the middle of the night. Any help is welcome!