This method will work on all versions of Windows 10, 8.1, 8, 7 and Vista. Let's see how can you reset Windows 10 Password in just a few steps.
How to Reset Forgotten Windows 10 Password with Installation CD?
Boot your computer from Windows 10 installation CD (If you don’t have Windows 10 install CD, you can use a Windows 8 or 7 install CD instead). When the Windows Setup screen opens, press SHIFT + F10 key combinations to bring up the Command Prompt.
Here we need to replace the sethc.exe file with cmd.exe. Just run the following commands at the Command Prompt one by one, replace d:\ with the actual drive letter of your Windows 10 installation.
copy d:\windows\system32\sethc.exe d:\
copy /y d:\windows\system32\cmd.exe d:\windows\system32\sethc.exe
When it's done. exit Windows Setup and remove the installation CD. Reboot your computer.
When your computer boots back to Windows 10 login screen, press the SHIFT key 5 times in a row. The Command Prompt will open with administrative privileges. Execute the following command and you can reset your forgotten user password quickly. Replace username with the name of your Windows account, and newpassword with your new password.
net user username newpassword
Close the Command Prompt and you'll come back at Windows logon screen. You can now sign in with your new password.
This method is also known as sticky keys trick and it can help you regain admin access to your computer when you're locked out of Windows 10, without using any third party software.