From: http://www.techrepublic.com/blog/tr-dojo/reset-windows-passwords-with-the-help-of-linux/

Sethc Hack: http://www.hackcave.net/2015/10/hack-windows-10-login-password-in-2.html

So let's get started.

1)Insert the live CD/USB and boot from it. [You may need to Turn off Secure Boot feature for UEFI BIOS]

2)Locate the drive where Windows is installed.(C drive) Goto Windows/system32 folder.

3)Find out a file named 'cmd.exe' and rename it to 'cmd0.exe'

4)Next, find another file by the name 'sethc.exe' [It is the program for windows sticky keys] Rename sethc.exe to cmd.exe.

5)Finally, rename cmd0.exe to sethc.exe. [Swapping the sticky keys program with Command Prompt (cmd). So whenever Sticky Keys program is called it runs cmd and vice versa. ]

5)Great! Now Shutdown and boot into Windows.

6)Press shift key five or six times at the login screen.

7)Now the command prompt will open up. Type this without quotes and hit enter.
"net user"

Now you can see the list of active accounts [User Names] in the PC. Make a note of the Account Name you need to hack.

9) type the following command and hit enter.
"net user <space><Account Name><space> *"

Note  <space>: leave space

          <Account Name> Replace it with the account you need to hack. In this example 'Mathews'

8)It will display 'enter new password'. Enter any new password and confirm. To remove password leave it blank.

Ubuntu Live on USB: http://www.ubuntu.com/download/desktop/create-a-usb-stick-on-windows

Rufus: https://rufus.akeo.ie/