How to remote shutdown the computer?

There are two XPPro Computer, which the name is xp1 and xp2.

I run the following command on xp1:

net use \\xp2 /user:administrator [the administrator password]
it replys with : The command run successfully

then I shutdown the xp2 computer by using:
shutdown -r -m \\xp2
But it replys with : The network path was not found.

What does it means?
And how to solve it? thanks