If you lost Windows 7 password and didn't have another administrator account or a password reset disk, you won't be able to get into your computer and reset the lost password. If there are no other user accounts on the computer, you can never use your computer again until you reinstall the system.
Therefore, the best way to keep your computer from dying and keep all data stored on it intact is to make a password reset disk by yourself to reset your Windows 7 lost password. How? Just follow the 3-step guide below.
To create a password reset disk, the first thing you need to do is to choose a program that can be burned into a bootable disk. Microsoft Media Creation Tool is such a kind of program, which permits you to enter the computer and reset the lost administrator password in Windows 7. You can use it in Windows 7, XP or Vista, and burn it into a CD/DVD or an external USB drive.
When you come to the Windows Setup screen, just press SHIFT + F10 key combinations to launch Command Prompt.
Type following commands in Command Prompt window and press Enter key each time you enter a command. Replace d:\ with the drive letter of your Windows installation.
copy d:\windows\system32\sethc.exe d:\ copy /y d:\windows\system32\cmd.exe d:\windows\system32\sethc.exe
Now you can close Command Prompt, cancel Windows Setup, restart your PC and remove Windows install disk.
After your PC restarts. At Windows 10 logon screen, press Shift Key 5 times consecutively and it will launch Command Prompt with administrator privileges.
Now, to change the password use the following command. Do not forget to replace 'username' with actual local account's username and 'newpassword' with the password that you want to set.
net user username newpassword
Close the Command Prompt and you can now log into Windows 10 with the new password.
Then restart the PC and get into the system, as usual, you'll find that the system doesn't ask for a password anymore, and you can enter to use the computer as before.
If you are going to set a new password on your Windows 7 computer to prevent unauthorized access, please make sure that the password you set is easy to remember so that you will not lose it again. By the way, here are 5 Windows password recovery tools that can also help you.