Type 'powercfg.exe/hibernate off' in the command line.If your Windows 8.1 PC still can't sleep, try 'powercfg.exe/hibernate off' to see whether it can help you.If your Windows 8.1 PC still can't sleep, try 'powercfg.exe/hibernate off' to see whether it can help you. Scroll down to find 'Power buttons and lid' option and click the + (plus) sign next to 'Sleep button action' to verify the action is really set to Sleep. The Edit Plan Settings box will pop out.Press Enter and click 'Change plan settings' in Power Options. Go to the Start Screen and type 'power options' in the search box.It is usually workable to put the computer to sleep by clicking Sleep, but sometimes the settings may change. when the troubleshooting has been completed, you can click Close.And this will start the automatic detection and fixing of issues. In the Power Troubleshooter, click Next option.Click Power option, which will launch the Power Troubleshooter.

After entering Troubleshooting, tap on 'View all' on the left side. Then click Troubleshooting in the listed results.

Press Windows key + W and type 'troubleshooting' in the search box.

You can run it to adjust your computer's power settings. The Power Troubleshooter checks things like the computer's timeout settings, which determine how long the computer waits before turning off the monitor display or entering sleep mode. Fix 'Windows 8.1 Won't Sleep' via Power Troubleshooter

In this part, I will introduce you three main methods that can be used to solve the problem 'Windows 8.1 PC will not sleep'. How to Fix Sleep Mode Not Working in Windows 8.1

Computer will not stay in sleep mode