Many people don’t regularly turn their computers off, instead leaving them to automatically go into sleep or hibernate mode until they next use it. While it is still good practice to properly restart your computer on occasion, using sleep or hibernate modes can be convenient for everyday usage. Unfortunately, computers can wake from sleep or hibernate mode unexpectedly at times, and this can become a major annoyance if you sleep in the same room as the computer. There are a number of reasons for computers having such sleepless nights, as explained below:

Determining the Cause of the Problem

Before you start modifying any settings, you’ll first need to determine the cause of the problem. Open the command line interface by pressing the Windows Key and “R” before typing “cmd” and pressing Enter. Type “powercfg -lastwake” (without quotes) into the command line and press Enter. The last device to wake your computer should appear at the top of the list. If nothing appears, you can try using the command “powercfg -devicequery wake_armed” to see a list of hardware devices connected to your computer which can wake it up from sleep or hibernate mode. However, this command will not tell you exactly which device is causing the problem.

Preventing Devices from Waking Your PC

In many cases, a certain hardware device will be the culprit, the mouse being the most common one. To prevent specific devices from waking the computer up, you will need to change some settings in the Device Manager. You can access the Device Manager by navigating to Control Panel > System and Security > System > Device Manager. Browse through the hardware inventory to find the offending device. Note that your mouse may simply be referred to as “HID-compliant mouse” rather than its actual model name. Double-click on the hardware item to open the Properties page, and open the Power Management tab. If you don’t see one, it means that the device in question does not support power management features and therefore cannot be the cause of the problem. Uncheck the box beside “Allow this device to wake the computer”.

Another device which commonly wakes up the computer, often at the most inconvenient of times, is the network adapter. You can find a list of network adapters installed in your computer by opening the Network Adapters tree in the Device Manager. Particularly if you are using a laptop computer, be sure to prevent network activity from waking it up by unchecking the appropriate box.

Turning Off Scheduled Tasks

It might not necessarily be a hardware component that is waking up your computer. In many cases, scheduled tasks can automatically start up your computer at unexpected times. If it is a program causing the problem, you’ll need to change a setting in the Power Options. Open the Control Panel and navigate to Hardware and Sound > Power Options > Change Plan Settings > Change Advanced Power Settings. Scroll down the list and open the Sleep section. Open the “Allow wake timers” tree and change the setting to “Disable” if it isn’t already. If you have hibernate mode enabled on your computer, you will also need to disable the wake timers for hibernate mode by navigating to the appropriate entry in the settings window.

Scheduled maintenance tasks may also wake up the computer. To prevent such tasks from happening, you will need to change a setting in the Action Centre. Open the Action Centre by clicking on the white flag icon in the system tray beside the clock and clicking “Open Action Centre”. If you can’t see the flag icon, you should be able to find it by clicking on the upward-pointing arrow beside the system tray. Open the Maintenance section and click “Change maintenance settings”. Ensure that the box is not checked to prevent scheduled maintenance tasks from waking up the computer.

While the above methods should fix the problem in most situations, it is still wise to properly turn your computer off at the end of the day. Even on sleep mode, your computer still draws a small but constant amount of power. Hibernate mode consumes no power, but it can also cause other problems including system instability when used excessively.