10g OEM URL problems

I am having trouble bringing up 10g OEM. I use comcast broadband at home and I connect to office network when I am in office. Both have different IP addresses. Also I sometimes use the laptop without connecting to any network at all and I installed 10g when the computer is not connected to any outside network.

I tried the localhost, 127.0.0.1, host computer name, officeIP and comcastIP and in all the cases OEM URL is refusing to come up.

Does anyone has this kind of problem before?

are you using the right url?

Did you use port number along with the localhost?