I skipped about 4 pages of this thread and since it appears to be just an educational thread now, as per VOS stating the OP is going to get a wired CCK installed, here's the best places to start.
Router Manufacturer and Model number.
IP, Gateway, and DNS address of a wired computer or item that is working properly
IP, Gateway, and DNS address of a wireless device that is working properly
IP, Gateway, and DNS address of item not working properly (in this case the IP of the WCCK and the DVR would be needed)
Confirm in the router that there is not a duplicate mac address for any connected device. (extremely rare and should technically never happen but I've seen it bring down the largest networks)
If all of these are correct then the problem is with device or the router. Rebooting the device is the first step. After that you have to look at wireless settings in the router itself. Today every software is designed to be "Plug n Play" which can actually make it harder to find out what the issues are because by default things can be setup that can cause issues.
Ping the non working device from a working device to ensure connectivity and routing. (This is a high level test you can do things like getting a port scanner and listen for the ports you want if you're so inclined but that's putting a 350 in a Chevette at this point)
If ping works then the router is routing properly to the devices. Now it's a matter of what settings the router has setup for wireless that wouldn't allow it outside of the network or that it isn't allowing the device to get that's needed.
A current trend is now having wireless network "guest areas" setup by default in routers so that when people come over they can connect to the internet without you giving your password out. They do limit internal networking functions. If this is on it can cause issues if the CCK is hitting that. If UPNP is on see what sessions are active. If there's an option of release or reset sessions on request do so.
Mostly if you get to the last step it's going to be finding out what software options exist and what is stopping it by default. Usually a quick google search will resolve this if you make your situation generic such as "New wireless device will connect to network but can't get to internet on WD 4300N".
I also didn't read if the OP had a WPS button or not and used that or if he manually inputted his settings.
In a nutshell at this point you either need to do 2 things with new routers. Leave them alone other than putting in a name and password for them or blast out every setting and set them up how you want them.
Oh also ask if there are kids or anyone in the house who like to download things a lot. If you have an avid torrent person they have probably setup rules in the router to streamline their setup for that and it can cause conflicts with other things.
Static IP's, Static port forwarding on a DHCP system without reservations can cause havoc if people aren't watching them and trying to setup new devices. Setting up a DMZ should really never be something that a home user wants to do unless they like to wear tinfoil hats as well. It can cause more issues than fix.
Edited by Shades228, 20 August 2012 - 04:00 PM.