Источник 1

HKEY_USERS\.DEFAULT\Control Panel\Keyboard

Find the string value called «InitialKeyboardIndicators». In Windows 7, set its value data to 2. In Windows 8 and above, set its value to 80000002. A note for Windows 10 users: if your Windows 10 does not save the state of NumLock after the reboot, try to set the value «InitialKeyboardIndicators» to 2147483650. This will turn on NumLock on the logon screen starting from the next boot.