Reset/Forgot Administrator/User Password with Command Prompt on Microsoft Windows 7/8/10.
Step 1> Boot the system with bootable media DVD/Pen Drive/Network.
Step 2> On Installation Screen Press Shift + F10 to open command prompt.
Step 3> Type diskpart to enter disk partition mode.
Step 4> Type list vol to know your O/S Drive Letter.
Step 5> copy c:\windows\system32\sethc.exe c:\
(In my case o/s present in c drive, press 'y' if prmpted)
Step 6> copy c:\windows\system32\cmd.exe c:\windows\system32\sethc.exe
(press 'y' if prompted)
Step 7> exit
Step 8> Restart or shutdown and start system without bootable dvd or pen drive.
Step 9> On login screen Press 5 times shift key to open command prompt.
Step 9> Type net user to find the list of users.
Step 9> Type net user wtc abcd123
(In my case wtc my user and abcd123 password)