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If you can log into Windows with an administrator account, you can easily change the passwords of any other account. If you are locked out of Windows or don't have access to an administrator account, see the next section. You'll need to do this even if you're already logged in with an account that has administrator access.  Windows 7 and earlier - Open the Start menu, right-click on "Command Prompt," and select "Run as administrator." Confirm that you want to open the Command Prompt. Windows 8 and later - Right-click on the Windows button and select "Command Prompt (Admin)." Confirm when prompted by User Account Control. net user and press ↵ Enter. This will display a list of user accounts on the computer. The accounts will be listed in columns based on their permissions level. net user username * and press ↵ Enter. You will be prompted to create a new password for username. You will have to enter the password twice to confirm it. The new password will take effect immediately. You can use the password you just created to log into that user's account. Log out of your current session and log in with the new password.

Summary:
Log into Windows using an account with administrator access. Open the Command Prompt as an administrator. Type . Type . Enter the new password. Log in with the new password.