Find out what woke your computer

Open a command prompt with admin privileges, and type the following command, and hit Enter: This will show you the last device which woke up your PC.  The second command is: This will show a list of all devices which can wake up your PC. The idea to run these commands is to understand the reason if it’s on the hardware level.

You can see from the list that there are three devices that can wake up my PC. You have the keyboard, mouse, and the Gigabit Network connection, i.e., Ethernet.

Windows 11/10 computer turns on by itself

If your Windows computer turns on by itself from Sleep at night or at any other time randomly, it can be a hardware or a software problem, and the resolution will depend on this. Here are a few suggestions that may help you. Some of these will need admin permission.

1] Disable Fast Startup

Windows 10 comes with Fast Startup mode which doesn’t turn off your PC the usual way. Instead, it keeps it in a mixed state so when you turn on the PC again, it is much faster. According to a few experts on the form, this can be an issue, and the solution would be to disable Fast Startup.

2] Prevent Task Scheduler from waking up the PC

Sometimes it’s more of a software problem, than a hardware problem. It is possible that you are using a Scheduled Task to get some of your work done at a specific time of the day or multiple times of the day. So we need to get rid of them, and instead of deleting those tasks, we can change the Power settings of Windows to make sure it ignores those tasks when on Standby or Hybrid mode. This will make sure that none of those programs can wake up your PC when it’s in sleep mode or shutdown mode. This applies only to Laptops. Read: What is a Wake source for Windows PC?

3] Disable Automatic Restart

Many a time the computer crashes, and the system restart itself. This is by design. If you have left your PC on standby, and this happens, the computer will restart, and if the problem repeats, this will keep waking your PC.

Type System on the Search bar.When it appears, click to launch.On the left, select Advanced system settings > Advanced tabClick on Settings under Startup and Recovery.Uncheck mark on Automatically Restart and click on OK.

4] Keyboard or Mouse Waking up your PC

The keyboard and mouse are some of the major culprits when it comes to waking up your PC. Maybe somebody just went by your PC, and slightly hit them, and your computer turns on. On my PC, I have set the keyboard to boot up my PC, and when my kid just pretends to be working on the keyboard, the computer comes alive. These devices come with a power management option, and you can disable it to make sure they don’t wake up your PC unless you really want to wake them up. Open Device Manager (Win+X and then hit M). This will list all the hardware on your PC. Select your mouse or the keyboard. Right-click and go to Properties > Power Management tab. Now uncheck the box which says Allow this device to wake the computer. Apart from the mouse, and keyboard if you are using any gaming rig to play games on your PC, you need to disable power options for them as well. You can figure that out with the powercfg –lastwake command we shared above. You will need to do trial and error to figure out which device is waking the device. Note: Make sure to have at least the keyboard or mouse to have the ability to wake up.  You don’t want to hit the Power button every time to wake your PC.

5] Wake on Lan

If your PC is connected to a network, Wake On Lan can also bring back your PC online. This feature comes in handy when a computer wants to communicate or send data or files to a network computer which should only come online when it is requested. Built into the hardware, i.e., network adapter, this could be one possible reason. If you check the screenshot where we ran the command, you will notice that we do have the ethernet adapter as one of the wake-up devices. Open Device Manager (Win+X and then hit M). Under Network adapters, find the one that was listed above. Do not change anything with those listed as Miniport. Right-click and select Properties > Power management > Uncheck the option which says ‘Allow this device to wake up the computer‘. This will make sure no PC on the network can wake your PC. However, make sure to remember this in case you need it.

6] Prevent Scheduled Windows Update & Automatic maintenance

Depending on your active hours or a predefined schedule, it is possible that its the Windows Update that has restarted your PC to complete the update. Windows also has an in-built Automatic Maintenance mode which wakes up the PC at the set time and performs all the updates on your PC.

Open Settings > Windows Update and Security > Windows Update > Select Active Hours. To change the time for Automatic maintenance, type Automatic maintenance in the search bar, and click on it. Here you can change the timing or just uncheck the box ‘Allow scheduled maintenance to wake up my computer at the scheduled time‘. I hope all these help you solve the problems which had been waking up your Windows 11/10 PC all of a sudden. A little more here:

Why is my PC turning on over a slight movement?

Some users put the PC in sleep mode and forget about it. When they come around it, and if accidentally a key is pressed, or the Bluetooth mouse moves a bit, the PC turns on. This is normal behavior, and we would not recommend disabling this feature; else you will have to press the Power button to turn it back on.

Why does my PC keep restarting?

If your PC keeps rebooting every time it comes back from sleep mode, then it’s a hardware issue. It can be because of a recent update that is not compatible with Windows. You will need to follow the linked guide to resolve it.

Can I leave my PC on sleep overnight?

Yes, you can but let’s not make it a habit. Sleep mode is useful when you need to keep a set of files open and come back the next day to resume quickly. However, once in a while, you need to restart the PC to clear off a few things stuck or when you need to update.