Problems Installing Microsoft PCI ethernet card

After installing a Microsoft PCI card my computer XP no
longer recognizes my broadband cable modem connection. I
contacted my ISP and they tell me that the problem is that
my drivers for this card have been "knocked out". Is this
possible and if so how do I restore them. I was using a
USB adapter which worked fine butafter installing the PCI
card it does not work either. I have uninstalled and
reinstalled the software several times but when it coems
tiem to recognize the componets I get and error message
saying it cand find the card. Device mangager says the
card is working ok.