I read your post and something tell me that the OS was not what came with the laptop. The issue with that is that drivers for the motherboard may have not been installed and Microsoft can't supply them. Try the laptop maker's web site for motherboard drivers or PC-Card slot drivers first.
Next, realtek doesn't make much more than the chip in the card. The error message is common in a laptop without motherboard drivers.
RTL8180L driver problem in a 802.11B wireless network card
I have a realtek RTL8180 chip in a wireless pcmcia card and am trying to run in win98 and the drivers (I even downloaded the latest driver from the website) will not work on my laptop running windows 98. I get an error that shows in the system properties the following problem for the Realtek NIC (network interface card):
ndis.vxd and ntkern.vxd device loaders could not load the device drivers for this device