There's usually two LEDS but some NICs have only one. The LED should light when a connection is established and blink when there is activity. Since your LED does not light up it is due to one of two reasons:
1) Your NIC is not connecting to your router/switch/hub, or
2) Your NIC is not functioning properly.
There is no software solution required at this point. You first need to get a connection to a router/switch/hub. Until that LED lights up there is nothing you can do on the software side to get your LC475 connected.