Please dont listen to anything people who think they know about computers tell you. Every thing they do works, but is temp fix. Just call Xbox and get the port numbers you need to open NAT. Then call whom ever made your router and they will help you set it up. Seriously you can listen to friends that think they know but it will just lead to more frustration when it just messes up again.
lol you dont need to call xbox live to get that information....the port numbers have been the same since xbox 1 and i have them.
UDP 88
UDP 3074
TCP 3074
open those on your router and you will then have an open connection in your xbox live
configuration.
lucky for you im a d-link preferred router user.
heres what you do, most models have the same menu
in your web browser type in 192.168.0.1
type in admin as user name and leave password blank, unless you already set the user name and password.
Find the Advanced tab, and then the firewall tab.
should be some boxes. type these settings in for each port.
Name- Xbox live 1
Action- ALLOW
Interface Source- LAN
Interface Destination- LAN
Ip Range start(next to interface source)- *
Ip Range end(next to interface source)- Leave it blank
IP range start(next to destination)- 192.168.0.1
IP range end (next to destination)- Leave it blank
Protocol- UDP
Port range- 88 and leave the second box blank
Schedule- ALWAYS
and just do the same thing for the other ports, but change the protocol to TCP for one of the 3074 ports.
My model is a DI-514 but the menus should be pretty close enough for you to follow these directions.