Are you using an external IP address or an internal one? If you're trying to use the one assigned you by your ISP there's a good chance this is the cause of the problem. Instead use the one assigned you by your router. So for example if I type "ipconfig" in a DOS box I see my router has assigned me the IP address 192.168.1.69. So http://127.0.0.1
should both have the same effect.