Power Button on Sign-in Screen - Remove or Hide in Windows 10
The Power button appears on the Sign-in screen in Windows 10. It allows the user to shut down and restart the PC. When supported by the hardware, the Power button menu also has commands to "Sleep" and "Hibernate". So, you can turn off your PC directly from the login screen without signing in.
You might want to hide that button to improve the security of your PC, so only authorized users will have access to the shutdown command. See how you can remove the Power button from the Logon screen in Windows 10. This can be done with a simple Registry tweak.
In detail: http://winaero.com/blog/disable-the-p...