My search to solve this issue became an unexpected quest. I will tell how I resolved this issue on my network in a moment.
First, I feel I need to explain, I tried everything, from Resetting the TCIP Stack. DNS Flush, DNS Release/Renew, Wisnsock reset, updating Driver, uninstalling drivers, uninstalling hardware - reinstalling hardware and drivers, Microsoft hot-fix for Windows 7, downloaded software which was ''supposed'' to fix the problem, deleting the Network, reconnecting to the Network, changing all the connection settings on the Adapter, disconnecting, reconnecting, changing channels on the router, rebooting the router to gain access on the devices for 5 hours tops, called At&t SEVERAL times, got a NEW router, ethernet cable, and...