Router will talk to computer but not to modem

I have a US Robotics Maxg wireless router and a D-link DC-200 cable
modem. My desktop connects just fine throught the modem. When I hook
the router up, my computer gets a private ip address from the router
but the router will not "talk" to the modem (no internet). I have tried
resetting and cloning the mac address, but ...no dice. Here's the
zinger, I have 2 nic cards on my desktop so I connected the modem to
the computer, shared the connection and connected the router to the
second nic card. Wireless internet works great that way. The problem is
that now the desktop has to be on all the time. I've established that
the router works. The modem works when connected to the computer. Why
won't they work together? My isp said the modem is sending a public ip
to the router. Any ideas?

On 2 Aug 2006 15:11:20 -0700, (E-Mail Removed) wrote:

> I have a US Robotics Maxg wireless router and a D-link DC-200 cable
> modem. My desktop connects just fine throught the modem. When I hook
> the router up, my computer gets a private ip address from the router
> but the router will not "talk" to the modem (no internet). I have tried
> resetting and cloning the mac address, but ...no dice. Here's the
> zinger, I have 2 nic cards on my desktop so I connected the modem to
> the computer, shared the connection and connected the router to the
> second nic card. Wireless internet works great that way. The problem is
> that now the desktop has to be on all the time. I've established that
> the router works. The modem works when connected to the computer. Why
> won't they work together? My isp said the modem is sending a public ip
> to the router. Any ideas?

You don't say who your ISP is so I'll take a guess. You need to power cycle
the moden whenever you change device connected to it. Your modem was
probably set up with the computer connected. Now you want to connect the
router to the modem but the modem has cached the mac of the computer.
Unplug the modem and wait several minutes for it to clear its cache. Power
up the modem and wait a minute or two for it to sync with your ISP. Power
up the router and wait for it to sync with the modem. Power up the
computers connected to the router.

I tried that...this thing has got me baffled. Maybe my modem is bad.