Network Controller Driver - Dell Latitude E6400

I have this Dell Latitude E6400 ATG, laptop running Windows 7 64bit, in the Device manager under other I hve 3 items with a Yelow  exclamation mark. 1: Network Controller, 2: PCI serial Port,  and 3: PCI Simple communications controller. I try to download drivers from Dell, still this three showing up with the yellow . I have a Netgear Wireless adaptor, I will see the Network Controller only when I insert the Netgear Wireless Card, I cant get the wireless card to get work. Any idea how can I get this thing working.

Thanks