|You probably need to install the drivers for your network card. You can confirm this buy checking in Device Manager.|
You should have those drivers on the CD that came with your motherboard.........if the network interface is built into the motherboard.
If it's a separate card, then you'll have a separate disk with drivers.
It matters not how straight the gate,
How charged with punishments the scroll,
I am the master of my fate;
I am the captain of my soul.