I want to Shutdown PC remotely

I am having 2 PCs in my LAN, One is running on windows XP Home edition and the other on windows XP professional. I want to remotely shutdown windows Professional system from my home edition PC. I tried and it failed. I downloaded PS Shutdown EXE and tried giving the professional administrator username and password but i was not able to shtdown remotely.

Later i downloaded LAN Scanner, and tried with dat tooo but still the same problem. The error is cannot access $ADMIN folder on the remote PC.

I could very well open in Remote Desktop. Any body help!