Windows 7: Xbox 360 Nat

Hello I been fighting with my router for weeks now. So here's the problem my Nat will not open. I've done everything from port forwarding and triggering to setting up DMZ. Nothing works. There was a few times where it would say it was open but next time I got back on it said it was closed. So can someone help me please? I need my Nat open.

Make sure you Xbox still has the same assigned IP address. I know mine will change from time to time. For example, when I got a DVR, I connected it to the internet. For some reason the router decided to make it 192.168.1.104, the IP address my Xbox had been. Now my Xbox is 192.168.1.107, so I had to change the portforwarding settings to reflect this. Also, make sure the following ports are open 53, 80 to 83, 87 to 89, and 3073 to 3076.

Well I looked into that and also open the ports and still nothing.