Shutdown using cmd command?

Question

i've tried 2 ways to try shutting down my friend's computer on the same network as me but always getting a "access denied". These 2 ways are : "shutdown –m \\computername –r –f –c “The computer will restart, please save all work.” –t 60"

and "shutdown -i". why i get access denied? im an admin on the computer i am using and my friend is an admin on the com he is using, why cannot????!!!

Answer 1

it is: shutdown

to restart type: shutdown -r