Can you please give us some more information as to the maker of the computer and Operating system etc?
I am sorry but this motherboard is supplied mainly as a Server unit and details of its specification are for business users only, so i cannot help much without the specification.
As I understand you have fitted the card and installed the drivers, after that it should show in the control panel/ network connections/, if you right click over the icon it should show "enable" or "disable", all you really should do is click on "enable" and that should be it. BUT!
are there any other network connections in the windows?
if so click on it and "disable" that other one then the "enable" should be cleared on the one you are trying to start.
sometimes if you have AOL installed it can make itself the only account connection.