Now that you've installed the hardware, you need to configure Windows to recognise and use the network card properly. This means Windows needs a "device driver" for the card, which is basically a piece of software that tells Windows how to control your hardware (that is, how to "control" your "device", hence the name). With any modern network card this should be simple - when you start up your computer, Windows should recognise that there's new hardware and look for drivers for it. Insert the driver disk that came with your card (it did come with one, right?!) and install the device drivers. If there's anything unusual about your card, eg the drivers are in an obscure directory on the disk, the card will (hopefully) have come with instructions on how to install the drivers.

If your card didn't come with drivers, the chances are that it will be compatible with an older card that Windows has device drivers for. Let Windows "search for the best driver for this device", and it'll probably come up with something like "RealTek…" or "3Com…". Whatever it says, just try it out - it will probably work!

If Windows didn't display any message about detecting new hardware, don't worry. You just need to go into the Windows Control Panel and choose "Add New Hardware" and follow the prompts. Let Windows search for new hardware.

With any luck it should now find your card and ask you for a driver disk - if you have one, use it, otherwise let Windows use whatever driver it comes up with (as above). If Windows still can't find your card, you're probably in trouble - the card may be faulty. Ask the vendor for help.

Checking that the card is there: Now go into Windows Control Panel and choose "System". In Windows 95/98/ME, go to the "Device Manager" tab; in Windows 2000/XP, go to the "Hardware" tab and click on "Device Manager...". Look for the "Network adaptors" section. In this section you should find the network card that you just installed (and on the computer that's acting as the server you should also see the network card that came with the cable modem). Make sure the card is working properly - click on the card and then click on the "properties" button. Windows should tell you "this device is working properly". If not, you'll need to work out why not - there may be a hardware conflict, or you may need to restart your computer, or you may be using the wrong device driver, or the card may be faulty. In any case, you need to have the card working properly (ie getting the message "this device is working properly") before you proceed to the next step. The following pictures are from the Windows 98 device manager; but it's very similar for all versions of Windows.