I just purchased a T40-W, activated it, logged into the Web UI using admin and created a new configuration. Now I cannot connect to the firebox again. What happened?
Did you change the IP addr of the firewall trusted interface?
If so, did you connect to the new IP addr in your web browser?
Is the firewall providing DHCP on the Trusted interface?
It is really hard to help without knowing what you set up for the firewall trusted and external subnets/IP addrs, and what else you conifgured.