There are three ways of turning a Windows computer off. If you turn it off the wrong way - with the power switch - over and over again - that can screw it up. The power switch is there for emergencies. Use it only to turn your computer on, not off. To turn your computer off these days and times, you need to tell it to turn itself off.
Here's how to do that.
1) The "fast wakeup" shutdown.
Click the START button in the lower left corner. On the big menu that comes up, directly above the START button is a strip of text that says "Start Search". To the right of that is a circle with a line through the top.
Click that circle for a fast shutdown. Your next startup will be faster. This shutdown closes your files and saves an image of your workspace. Your computer will start very quickly again, because it knows what to do. But the computer must stay plugged in.
2) The "full shutdown".
Click the START button. To the right of the circle with a line in it, you see a lock and a triangle. Click the triangle. Select "Shut Down".
The full shutdown gets all the kids dressed in their jammies and put into bed before it turns out the light.
If you ever have a problem, you may be able to fix it by restarting the computer and going through a full shutdown. The full shutdown is a healer. Good to do before you unplug the computer.
3) The power switch.
Use this only when you lose control of the mouse and keyboard.
On a computer, the power switch is a rescue switch. Once you have used the power switch you will need to restart the computer and put it through a full shutdown to make it ok again.
For other equipment that you turn off, you just flip the power switch. The same switch that turns it on, turns it off. You would think that this would be true for a computer. But for a computer, this is an emergency turnoff. It leaves a lot of work undone. It doesn't 'put the computer to bed'. Any program in use is left half finished, with files open. Any data in memory that needs to be written to those files is lost when power is switched off. Files can be broken. Using this switch all the time can screw things up.
So use number 1 or number 2 above, and your problems may fade away.