This works on Windows 7, Windows Server 2012, but I’ve not tried on other platforms.
First off fire up a cmd prompt, with administrative privileges.
Then into this type the following:
net user account_name *
This will prompt you for your new password, which will not be displayed, and then to verify it afterwards as well.
Automatic Logon Into Windows 7/10/11
Press Windows key and R, a command box should appear.
Into this box, the “Open:” field, type control userpasswords2
and hit the enter key.
This should display the “User Accounts” screen, in Windows 7. From here select the user name, in the main table, and uncheck the “Users must enter a user name and password to use this computer.”
A click on the Apply button will open the “Automatically Log On” window. Enter the password, and confirm it, to add the password to the system so that it does not need to be entered during startup.
17-Aug-22: A Windows 10 update has removed this functionality, so on new installs you will not see the checkbox anymore. To re-enable it you need to fire up regedit and then navigate to:
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\PasswordLess\Device
Then change the value of DevicePasswordLessBuildVersion
to 0.
Restarting the command will now show the missing checkbox.