Most laptops with built-in Wi-Fi utilize a mini-PCI slot to support this type of card, making it fairly easy to install. In some cases, you can install an external wireless card into a PCMCIA or ExpressCard slot, but this requires an extra component sticking out of the laptop and is not ideal for most users. If you have a laptop with a failing Wi-Fi card it may be time to purchase a new network card. Although these are general steps for installing an internal laptop wireless LAN card, they should apply to most notebooks.

1. Remove the battery and disconnect AC Adapter

Before doing any repair work on a laptop, be sure to shut down the computer, unplug it from the wall, and remove the battery. This will help prevent static discharge while working on the machine.

2. Find the access panel and remove

Most laptops with a wireless card slot have an access panel that provides easy access. In most cases it will be a square panel on the bottom of the laptop. Remove screws and remove the panel. In some laptops the Wireless LAN card is located underneath the keyboard. There will be two metal clips on either side of the card edges holding the card down in place, release these and the card will pop up and can be removed.

3. Remove old Card / Insert the new card

Remove the old card from the Mini-PCI slot on the mainboard and compare it to the replacement, be sure they look very similar in shape and that the connections are the same. Line up the pins and insert it at a slight angle, press it into the slot and then slowly lower it until it locks into place.

4. Connect the antenna(s)

If your laptop has one or more antenna cables inside the access panel, you can connect these to the wireless card for better reception. Most cards have an antenna connector labeled "Main" and another labeled "Aux". Again, the connections should match your original card or you may have compatibility issues later.

5. Reassemble

Replace the access panel and screws and replace the keyboard if it was removed and secure all screws removed during disassembly. Replace the battery and reconnect the power cable.

6. Configure Wi-Fi Settings

If you replaced the defective card with the exact model that was originally in the machine, there will likely be no configuration needed. If it was a different model, you may need to reconfigure your Wi-Fi settings in Windows to allow you to connect to your wireless network.

Test to ensure the card is working properly and that you are able to connect to a wireless network. If you are sending and receiving correctly then you are finished with the installation, otherwise you may have to revisit the settings in Windows to confirm they are correct for your wireless network. If the card is not recognized by Windows, that may point towards the card not being installed correctly or a defective card. Retrace the installation steps to confirm the card is seated properly and all antenna wires are connected firmly.