Disclaimer: This will wipe all of the data except for the operating system off of the computer. If there is data on the target computer that you need then you will want to find a way to get access and back up the computer before you do the factory reset.
Why Do A Factory Reset
There are plenty of reasons to do a factory reset. Sometimes a system gets bogged down over time or gets infected with a virus and it is simpler just to start from scratch than to diagnose individually. Other times you may have simply forgotten your password and need to start over to regain access to the computer. Whatever your reason, the process of doing a factory reset on Windows 8, 8.1, and 10 has become much much easier and it doesn't even require administrator access.
How To Factory Reset A Windows 8, 8.1 or 10 PC
1. Find where the power button is for you in your operating system. This is the button you usually press to get the logout, shutdown, restart options. If you are not logged in then you will find it in the bottom right.
2. Once you have found this button, click on it so that it shows you the various options. Now hold the shift key on your keyboard and click on the restart option. This should lead you to a screen that has a few options
3. Click on the option that says "Troubleshoot"
4A. Windows 8 or 8.1 Now if you are on Windows 8 or 8.1 you will see the options Refresh or Reset Your PC. Refresh will try to correct errors in your Windows install and return many settings to default as well as remove some apps, but it will try to keep all of your files in place. If you do not have access to the computer or if you are trying to prepare the item to sell then this is not what you want. If you just want to see if it can fix some minor errors in Windows then it is likely worth trying this before you do a full wipe.Reset will return Windows to factory settings and remove all files and apps. This is likely the option you want if you are preparing to sell the system or want to do a full wipe to regain control of the system.
4B. Windows 10 If you are on Windows 10 then you will be given the option to reset your PC. Click this and then You can choose between keeping your files or removing everything. The keep files option is the same as refresh was for Windows 8 and 8.1. If you choose this then Windows will make an effort to correct errors in the operating system as well as remove some apps but try to keep the files. If you are just trying to correct some errors, but want to keep the data then likely this is what you want. The remove everything option will wipe the computer all the way to factory settings. This will remove all apps and all files and make it so you have access to the computer again if you do not currently have a password.
5.The computer will restart a few times now and if you chose the reset option in Windows 8 or remove everything in Windows 10 then you will be left with a computer that is configured just as it came from the factory and is ready to be setup for the first time or sold.