DSL at home, Cable at office- can't go back and forth

I have two Dell Inspiron 5150 laptops. The network at my house uses a DSL connection, which requires DHCP to work. The network at my office uses Roadrunner cable, which requires fixed ip addresses, DNS servers, etc. If I take the laptops home and turn on the DHCP, they can access the internet, no problem.

However, after taking these two computers back to the office, turning off DHCP, and re-assigning the fixed IP addresses again, these two laptops are unable to access the Internet although the computers can see, and be seen, on the LAN just fine. I have checked and re-checked the settings, and I know they are right. I also made sure that the "enable netBIOS over TCP/IP" radio button is checked. (With DSL, I set that to the default)

Obviously, I'm missing something. Any ideas?

There are four basic values you have to tell your networking subsystem when putting a standard computer on a standard Internet-connected network:

1. IP
2. DNS server(s)
3. Gateway
4. Broadcast or netmask

As for #4, Windows has an ability to figure these out given other information, but more often than not, it screws them up. I put them on the same line because you really only need one to figure out the other.

The gateway (#3) is the computer through which your network traffic goes to get to the Internet. My guess is that you haven't set this up. It would certainly explain why you can see the rest of your network but not outside it.

Colin

Thanks for your reply.

The gateway is set up properly; the other 15 computers on the network can access the Internet with no problems.

The only thing I don't understand is "broadcast or netmask". Is that the 255.255.255.0 number?

The netmask is going to look something like 255.255.255.0. The broadcast address looks something like 192.168.0.255.

Colin