Q: For some reason I can’t get my laptop to connect via Wi-Fi on my home network anymore. Any suggestions? — Andrew

A: Networking issues have always been one of the more problematic areas in the tech world because of all the complexity and the introduction (and popularity) of wireless networking has made it even more problematic.

I have, for eternity, preached that ‘wired’ is always better than ‘wireless,’ but that isn’t always practical or convenient. If you can convert to a wired connection without impacting the practicality of using the laptop, then you could eliminate all the headaches that can seemingly pop up out of nowhere with wireless connections.

Wi-Fi networks operate in an unregulated frequency range, so at any time a neighbor’s new wireless router, your microwave oven, cordless phones, or even ‘nanny-cams’ can cause interference with your computer’s wireless connection.

Here are the most common variables that have to be diagnosed in order for you to troubleshoot this common situation: your wireless router (or access point), your laptop’s wireless adapter, your laptop’s network device drivers, your laptop’s overall health, the security levels set up on your router, and the security settings on your laptop.

The quickest way to determine where the problem resides is to try using your laptop on a completely different wireless network and have a friend bring their laptop over to try to connect to your wireless network.

If your laptop works on another wireless network, then you can eliminate your laptop’s wireless adapter, the general health of your laptop, or any associated driver issues.

If you have trouble connecting to another wireless network, then you can focus your troubleshooting attention on your laptop. If you plug your computer into a wired ethernet connection and it works, then you can eliminate the overall health of your laptop and it narrows the problem to either a defective wireless adapter on your laptop or improper configuration (which can sometimes be fixed by reloading the software driver from the manufacturer’s Web site).

If another laptop also has a problem connecting to your wireless network, the problem is likely in your wireless router (or access point) or some other wireless device that is causing interference.

Wireless routers do go bad over time, especially if they are on top of another heat generating device, like a cable modem or an older CRT monitor, so if you’ve had your wireless router in that type of environment for a couple of years, then replacing it may be your best bet.

In some cases, you can update the ‘firmware’ for the wireless router by downloading a firmware update from the manufacturer’s Web site, which can solve known reliability issues and return it to service.

The other possibility is that the security level (generally known as the encryption level) is set too high and therefore less compatible with devices from other manufacturers.

The easiest way to test this segment of your wireless network is to disable the encryption in the router and in your laptop’s wireless adapter configuration, making your router easily accessed by anything in range. If you can connect with no problem, then you may have the encryption level set too high (lower it from 128-bit to 64-bit, for instance) as the more complex the encryption routine, the more likely you will have a problem, especially if you are using adapters and routers from different vendors.

By following a logical progression of tests that eliminate one of the areas of the network you can eventually narrow down the area of the network where the problem exists: router, laptop, or environment.

Ken Colburn
Data Doctors Computer Services
Data Doctors Data Recovery Labs
Data Doctors Franchise Systems, Inc.
Weekly video tech contributor to CNN.com
Host of the award-winning “Computer Corner” radio show