DELL-Larry R
4 Germanium

Re: New DSL modem installed

It is my guess that the working comptuer is connected via USB.  In my experience, cable and DSL modems with both USB and ethernet ports will automatically disable the ethernet port if a computer is connecting using a USB cable.

If both are using ethernet, however, then more testing would be needed.  A simple solution would be to get a router between the computers and the modem.