Hardware Internet NAT problem

[laurorual]

I have a Xbox 360 phat and we'll, it doesn't have a wireless adapter build in, so I have to use the Ethernet to connect it to the Internet. The thing is, my router(I think it is a gateway) is in another room. When I connect it through wire connection direct to the router, my Xbox can connect in Live with no problems, but when I tried to make a bridge connection between my laptop and my Xbox I always get a message saying that I have NAT error. I've tried open port on my router, change the network wire, change settings in my laptop, deactivate the firewall and still getting this NAT error. Can someone explain to me why I'm getting this error while making a bridge between my laptop and Xbox and not when connecting it directly to the router?

 

[DinohScene]

Problem lies with the networkbridge.
Iirc it's unavoidable.

 

[solitaire4eva]

Create a static IP and open up a specific port. That's what I did and it started passing all parts of the xbox connection test.