Wireless internal cards
Some systems have optional internal wireless cards. When you order the system with the wireless internal card, the factory installs an antenna for the wireless card. If you ordered the system without the internal wireless card and decided to add the card later, you may not be able to add the antenna. You will be able to install the card but it will not pick up a wireless connection without the antenna. On some systems, you are unable to add the antenna after you purchase it.
If you ordered a system without the internal wireless card and unable to add the antenna, you will have to use a PCMCIA network card instead.
The advantage of the internal card over the PCMCIA and USB version is that the PCMCIA sticks out on the side of the portable. The USB version is also plugged to the portable. The internal card doesn't. This means you have to remove the PCMCIA card to store the system in the carrying bag. If you have no antenna for the internal, you will have to use the PCMCIA or a USB version.
If you are having an issue with the internal device, try uninstalling the driver and then reinstall the driver.