Grant sudo acces to script without asking for password
Granting the user to use that command without prompting for password should resolve the problem. First open a shell console and type:
Then edit that file to add to the very end:
username ALL = NOPASSWD: /fullpath/to/command, /fullpath/to/othercommand
john ALL = NOPASSWD: /sbin/poweroff, /sbin/start, /sbin/stop
will allow user 'john' to sudo poweroff, start and stop without being prompted for password.
Look at the bottom of the screen for the keystrokes you need to use in visudo - this is not vi by the way - and exit without saving at the first sign of any problem. Health warning: corrupting this file will have serious consequences, edit with care!