Help--can connect through cable modem but not through router

[Saltynutz]

OK, I need massive help.

I have two computers. I have a cable connection to the internet. Both computers work great on their own connecting directly to the net via the cable modem.

However, once I try and put a router in between them so both computers can use the net at the same time, while one still works, another just simply cannot connect to the internet.

On the problematic computer, I've tried changing out network cards (I bought a new Linksys network card to try and match the Linksys router I was using on the theory that there might have previously been compatabaility issues), I've made sure TCP/IP is installed, I've compared the network card's setting to those of the computer that works and they seem equivalent, I've tried two different routers.

I need help mates. Why won't a computer that can connect directly to the net via a cable modem not connect through a router, while what is a seemingly identical computer configuration on another computer works fine either way?

Please help. Thanks

 

[earnhardt2]

How is your router set up? Any security? Can you give any more info about your setup? I'm assuming DHCP is set up on both computers and both the router is set up as a DHCP server for the computers. I'm also assuming that there is no MAC address filtering, or other security measures. Does your computer that won't connect get an IP address? I would check that first. If not, then check your router settings. If so, then check any firewall, any proxy server, and other security software that might be preventing your computer from connecting. If so, then try to ping the router. If you can't, then you need to look at your router settings as that would probably be where your problems lie. If you can, then try to ping a website. If you can, then check your browser settings. If not, then double check settings on your computer and router. Try this and post about how far you can get.

 

[maury73]

Make sure you have setup-up the default gateway to the router's IP address.

 

[sturm]

Unplug the power from the cable modem and the router. Turn on cable modem, wait about 15 seconds then turn on the router. Wait about 1 minute and then turn on the computer. This should reset the router and modem to talk to each other. Anytime you switch from directly connected to the modem to the router you need to reset both of them.
If an install disk came with the router be sure to run it on both computers.

If this doesnt work then make sure both computers are getting an ip address by typing ipconfig /all in a command prompt window. The default gateway should be something like 192.168.1.1 or maybe 192.168.2.1.
Also check the dhcp settings on the router like earnhardt2 said and also that the computers are set to auto detect settings.