You might have changed your user name and passwords so many times, but if you haven’t yet tried this using Command Prompt, here we have given the way to do that.
•    First go to Start Menu and choose Run.
•    In the command prompt, type “net user” without the quotations and press enter.

•    Now you will have all of the account names and details.
•    Now type “net user and the user name you want to change” without the quotations and press enter.

•    Now the prompt will display complete details about the account and the password.
•    Then if you type “net user and the user name between the stars” like “net user *XYZ* you will get more information about the user to control it.

•    But you don’t need to do that. Just type “net user and the username *”. For example “net user XYZ *” and press enter. (You should have a space after the user name)
•    Now you will be prompted to enter a new password.
•    When you enter the password, your cursor wont move, so don’t worry.
•    After typing the password, press enter.
•    Now again you will prompted to enter the same password for confirmation.
•    Retype the password and press enter.
•    This is smart enough to change the password using command prompt.

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