Do you know if there are any other wireless networks that could be interfering with yours? Or is his computer connected to a DHCP server through his isp that needs to be disabled.
Go to Newtork Connections ->LAN connection( or which ever one is hard wired) ->right click ->disable, or disconnect.
Even if there is a small signal that is being picked up the DHCP server will have a problem.
You can do a trace route, in command if you need to find where the ip is coming from on his computer, too, if needed.
LEARN BY DOING NOT BY FOLLOWING DIRECTIONS!
I thought you were a hispanic/african american? Who is the white guy in the pictures?