Q&A for How to Access Your Computer if You Have Forgotten the Password

This is entirely dependent on your version of Windows, as well as the level of access you have. I would always recommend wiping and reinstalling Windows when you get a used computer.

Reboot the computer and press "F8" before the Windows screen initializes. A boot option menu will appear. Select "Safe Mode" from the list of boot options and press "Enter." Allow Windows to boot up automatically. Log in as the Administrator and click "Yes" when the message to continue in Safe Mode appears. Click on the "Start" menu button, select "Control Panel," and then switch to Classic View. Click on the "Users" icon. Select the user account whose password you forgot and need to change. Select "Change Password." Type in the new password, confirm it and click "OK." Reboot the device and allow Windows to boot up normally. Type in the new password to log in.

Get onto another computer and find some kind of password bypassing software. Put it on a flash drive and put that into your computer.

It will always exist, but most likely not have its own visible account. Create another account, then access the other account through sudo command on the command prompt.

If you have signed in to W8 using a Microsoft account (you log into the computer with ***@***.com and not just a username like "jim"), then you can reset your Microsoft account password online. As long as your PC is connected to the internet, you can now log in with your new password. If you created a local account (just "jim" for example), then you're most likely out of luck. Unlike Windows 7 and previous versions, Windows 8 and 10 have their system files protected, making it impossible to recover the password while outside of the OS, which you can't get into without a password.