I have two computers in my office that, much like disgruntled toddlers, won’t stay asleep. I click the Sleep button, wait for all the fans to stop spinning, and find myself woken up by the blinding lights of my motherboard at 2 a.m. If this sounds like a familiar story, here are a few ways to diagnose the problem and keep your computer down for the night.
Find Out What Woke Your Computer
Windows knows what woke up your computer most recently, so the next time it wakes up unexpectedly, open the Start menu and search for “cmd,” then right-click the Command Prompt and choose Run As Administrator. Type the following command and press Enter:
powercfg -lastwake
If you’re lucky, it’ll give you a pretty clear answer. For example, the last time my workstation woke up, it was due to my cloud backup program running its scheduled backup for the evening. In that case, your search is over, and you can adjust that program’s settings or uninstall it to stop the problem.
In other cases, it may list a specific hardware device, and you can skip down to the relevant section in this article, or do some extra Googling on what settings to change on that device.
If that command didn’t give you useful information, try this one:
powercfg -waketimers
I’ve also had luck searching Windows’ Event Viewer for information. Click the Start menu, search for “Event Viewer,” and launch the tool. In the sidebar, head to Windows Logs > System, then click the Filter Current Log button on the right side of the window.
Choose Power-Troubleshooter from the Event Sources drop-down menu and click OK to see all the times your computer woke up recently and what caused them. Filtering by Kernel-Power may help too, but in my experience, it’s less likely to include useful data.
Using that information, you can try some of the solutions below to keep your computer from waking up randomly next time.
Tweak Windows Update, Scheduled Maintenance
Windows Update is a fickle beast, and I’ve had it cause numerous unwanted wakeups in the past. There are a few ways to solve this problem.
First, try using Windows Update’s built-in tools to more meticulously schedule those updates and reboots. Set your Active Hours and Reboot times and defer updates until you have time to install them, and you may be able to solve this problem easily. To dig a little deeper, though, you will need Windows 10 Pro or above.
With the right version of Windows 10, open the Start menu, search for “Group Policy,” and head to Computer Configuration > Administrative Templates > Windows Components > Windows Update, then double-click Enabling Windows Update Power Management and set it to Disabled.
Windows also runs an Automatic Maintenance set of tasks once per day, which it says includes software updates, security scans, and other jobs. Open the Start menu, search for “Scheduled Maintenance,” and open the resulting option.
You can either change the time this runs—I have mine set to run at 5 p.m.—or prevent this from waking the computer altogether by unchecking the box at the bottom.
Find a Misbehaving USB Device
If Windows tells you a USB device is waking your computer, you’ll have to find the offending device. I’d bet dollars to donuts it’s your mouse or keyboard—maybe your cat thinks it’s a fun toy when you aren’t looking—but it could be anything.
If you have trouble figuring out which device is the problem, remove all your USB devices the next time you put your computer to sleep, and see if it wakes up on its own. If it doesn’t, you can leave one device plugged in the next time you put it to sleep. Keep doing this until you find the offending device.
Once you find the problematic hardware, open the Start menu and search for “Device Manager.” Find the device in the resulting list—say, your keyboard—and right-click on it. Select Properties and the Power Management tab, then uncheck the Allow This Device to Wake the Computer option and click OK.
If your computer doesn’t stay asleep after this, you might also try entering the BIOS and disable USB waking from there, if you see an option for it. (You can enter the BIOS setup by pressing a key when your computer first boots, usually something like Delete or F2—the boot screen will usually tell you.)
Limit Your Network Adapter
One of my insomniac computers told me that it was waking up thanks to an Intel(R) I211 Gigabit Network Connection. That’s the Ethernet port that connects my computer to the internet, and it means some sort of network activity is waking the computer up regularly. You can fix this from the Device Manager.
Open the Start menu, search for “Device Manager,” and find the Ethernet or Wi-Fi adapter in question under Network Adapters. Right-click on it, choose Properties, and open the Power Management tab. Uncheck the Allow This Device to Wake the Computer option, and you should be golden. You may also find network wakeup options in the BIOS, as described in the section above.
Alternatively, you can keep that box checked, and check Only Allow a Magic Packet to Wake the Computer. This is useful if you use Wake-On-LAN to access sleeping computers remotely. It’ll ensure that Wake-On-LAN still works, without allowing just any network traffic to rouse your computer from its slumber. This box isn’t checked by default, for some ungodly reason, and checking it solved my problem beautifully.
Disable Other Wake Timers
If none of the above fix your issue, you may have to dig into the wake timers set on your computer—that is, scheduled events that are allowed to wake your machine. Open the Start menu, search for “Edit Power Plan,” and click Change Advanced Settings in the Edit Plan Settings window.
Head to Sleep > Allow Wake Timers and change both Battery and Plugged In to Disabled. You’ll want to repeat this process for all your power plans in the drop-down menu at the top, not just the one you’re currently using.
Here’s the thing, though: this is a sweeping setting designed to affect all wake timers, which may mean it’s too overzealous for you (if you have certain wake timers you want turned on). It’s also weirdly ineffective, which means even if you do want to go nuclear on wake timers, it may not stop them all, but feel free to adjust it anyway.
With that in mind, I also recommend opening PowerShell and running the following command:
Get-ScheduledTask | where {$_.settings.waketorun}
This may help you find scheduled tasks designed to wake up your PC. If you find any you want turned off, open the Start menu and search for “Task Scheduler,” then navigate to the task in question using the sidebar, and double-click to edit it. Select the Conditions tab and uncheck the Wake the Computer to Run This Task box.
Random wakeups can be incredibly finicky to solve, and you may find that even more digging is required to find your specific issue. But hopefully the above options have at least pointed you in the right direction.
Keep in mind that you may have to go back and do this in a few months if it starts happening again—new programs, new hardware, and Windows updates can always cause the problem to resurface. It’s a curse, but at least now you can keep it under control.
