My computer can not connect to my ATT DSL gateway. Although it is shown connected in the local area LAN, I could not go into the internet. I thought it was the system problem so that I had completed reinstall the whole operating system back to win xp sp1. However, it does not solve the issue. I uninstalled the network adapter a few times. still no luck. I can see the my private IP address and gateway info from local area connection. Is there anything I have to manually configure after reinstalling the whole system? Please Help!
Your ATT DSL gateway is "outside the box" as it is said. Your computer probably has nothing to do with this problem.
The ATT DSL gateway should have a configuration Cd with it. You are probably not Authenticated with AT&T going out the DSL circuit.
Most DSL systems use PPoE and that usually means a log-in is needed. You need to access the gateway directly (no routers in use), and
authenticate your log-in with the AT&T system. This will require your user name and password. Some routers have a means of storing
your DSL log in information and will do this for you as needed, but now you need to establish your original connection with AT&T using the
minimal, basic setup possible. Since you are apparently somewhat proficient in working with Windows, access the gateway and see if it has
a built-in html page for doing setup. Follow instructions, supply needed info.
enter "CMD" (minus the quotes)
enter "ipconfig /all" (minus the quotes)
see what it shows as your default gateway IP address
Open browser, go to the default gateway address (found from ipconfig) and see if it answers. If it does, have all your log in
information ready and enter where appropriate. Things should work now, until the next time you dis-connect the DSL gateway
or something else severs the DSL connection with AT&T. Once the authentication is complete, you can connect a router between
computer and DSL gateway, just don't disconnect the phone line or power to the gateway. Thus it is good to have a router that supports PPoE.