Step-by-Step: Connect a Second Computer to Your Home Network Setup

Home network setup:

So, you’ve got your High Speed Internet service up and running on one computer. Now comes the moment of truth — connecting your second (and third, and so forth) computer to your home network setup. Where do you get started? Can you really do this yourself? Can you map computers on a network to different network cards? Yes, you can. Just follow our simple guide.

Step 1. First, does your computer have a networking card already installed?

Before we can do anything, we have to first figure out whether it has a networking card in it already. Chances are, if you have purchased your machine in the last three years, or if it is a Macintosh, it has a network card inside. But to be sure, let’s check the back of the machine and look for an RJ45 plug, which will look something like this:

Home network setup - back panel
In the photo, the RJ45 network plug goes in the top row, third from left.

If you aren’t sure, take one end of the Ethernet cable that is attached to your first computer and see if it fits. It could be the smaller plug for a modem, which isn’t the same thing at all.

If you have a network card in the machine, skip to step 3 to set it up. If you don’t have a network card, go to the next step.

Step 2. Wired or wireless?

Home network setup

If you don’t have a network card inside, or if you can’t easily get a wired connection to the location in your home that you want to use this second computer, then you need to add a wireless adapter to it, and set that up. You’ll also need to make sure that the network firewall/router that you purchased has wireless access as part of its feature set. (See article #4 for more information about purchasing these kinds of products.)

Many different kinds of wireless adapters are available; we’ll look at two of the more popular kinds. You can either purchase a wireless card that fits inside your computer, or one that connects to the Universal Serial Bus (USB) plug on the outside of the computer. For example, Linksys makes several different kinds of wireless cards, such as this one (left) for inside computers:

Home network setupAnd this one (right) is for outside, USB connections:

Both of these wireless adapters cost roughly $50. Which kind is better? Both will do the job. Obviously, the USB adapter is easily connected to your computer without having to open it up. However, if you are concerned about performance, such as for a gaming machine, then go with the internal adapter.

If you are buying wireless connectivity for your computers, take several factors into account. First, both the router/firewall and the adapter must make use of the same wireless transmission scheme to work together. Most of today’s products use the 802.11g standard, although some of the newer products make use of 802.11n standard, which is somewhat faster. For a beginner, I recommend the 802.11g because it is more stable and the products from different manufacturers work well together. For 11g, you can generally use different manufacturers; for 11n, stick with the same vendor.

Second, your firewall/router should be located in the best possible place in your home. (See Step #9 for tips here.) If you are going wireless, it needs to be located as high as possible to get the best signals.

If you are going to connect this second computer via a wired connection, then, obviously, you need to make sure you have long enough cables to connect both computers. You can buy patch cables at Best Buy, Circuit City, Radio Shack, and other electronics retailers.

Once you are done with the actual wiring, go to the next step.

Step 3. Configuring your network adapter

Whether you have wired or wireless, you need to configure your network adapter with the right components to work on your home network setup. In many cases, the standard settings will work just fine. But I’ll show you how here.

For a Windows machine, you want to get to the control panel that allows you to setup your network for the TCP/IP protocol. Depending on the version of Windows you have, there are somewhat different paths to get there.

For Vista:   Go to Start > Control Panel > Network Connections > Manage Network Connections. That will bring up another window listing the various network adapters installed in your machine.

For XP: Go to Start > Control Panel > Network Connections > Local Area Connection.

For 2000: Go to Settings > Control Panel > Network and Dial-up Connections > Local Area Connection

For 98/Me: Go to Control Panel > Network

For Windows 95: if you are still using Windows 95, now is the time to toss this computer and buy something new.

However you get there, using the right-hand button of your mouse, choose the “Properties” button. You should see a screen something similar to this:

Home network setup

The critical place here is the box of items in the center of the panel. It should have at least the Internet Protocol (TCP/IP) (Vista calls it TCP/IP version 4) among the listed items. The others are less critical. Highlight this entry with your mouse and click the properties button underneath, and it should look like this:

Home network setup

The key thing to note in this screenshot is that the button at the top that says, “Obtain an IPC address automatically” is chosen. That means that you won’t have to worry about setting this up any further once you have your router/firewall configured properly.

If you are running Windows 2000 or Vista, your screens will look mostly like the Windows XP screens that we have reproduced here. Older versions of Windows will have somewhat different screens, such as the one below:

Home Network setup image

If your screen looks like this, you need to change it. You’ll notice that this screenshot shows your TCP/IP Properties with a specific address of four numbers. What these numbers mean isn’t that important right now, but you want to click on the top-most button (to obtain an IP address automatically) if it isn’t already showing that way.

Vista adds two new elements to the networking controls. First is a network map that shows you a diagram of the computers on your home network setup. It is a handy way to determine if you have connected up all of your computers correctly. Second is a routine called “Diagnose and Repair Network Connections” to help with your troubleshooting.

Macintosh networks

Let’s look at what needs to be done if you have a Macintosh. Chances are it is setup correctly, but doesn’t hurt to check. Note that if you’ve installed a wireless router, your Mac should recognize it upon startup via AirPort. If you are running OS X, go to the System Preferences control panels, and then choose Network. At the top of this screen, choose Automatic for the Location, and Show: Built-in Ethernet. You should then highlight the TCP/IP tab and the next line below it should read: Configure IPv4: Using DHCP. The screen should look like this:

Home network setup

If you are running Mac OS 9 or earlier versions, you will see a screen something like this when you go to the TCP/IP control panel:

Home network setup

For these computers, you want to choose Connect via Ethernet, and Configure: automatically for setting up your IP address.

Step 4. Configure your firewall/router

The last step in getting your network set up for Internet access is to make sure that your firewall/router is communicating with your computers. The router supplies the IP addresses, and most of the products you buy today are configured to do that automatically, provided you have plugged the Ethernet wires in the right places. They should be marked “LAN” or have numbers from 1 through 4, or “Ethernet” or even “Connections to Computers” or some combination of these labels. What’s important is that the Ethernet cable is firmly connected to the receptacle, rather than which of the network ports are connected to which computers. Typically, once you place the cable in the right place, a small light is illuminated above the cable, indicating a connection.

Here is a photo of some common routers and what they look like on the back, where you plug things in:

Home network setup routers

In the future, we will have other articles that describe how to enhance router security and more advanced activities. For now, we are just discussing the connection itself. Once you have plugged in the wires, go back to your computers. Make sure they are off, and then power them back on, bring up a Web browser, and make sure you can get out to the Internet, by going to a site such as to If you cannot, then proceed to the troubleshooting steps below.

Step 5. Some troubleshooting tips and tricks for your home network setup

There are many places where things could go wrong in setting up your home network. While I can’t cover every situation, here are the most common ones.

Your Windows computer doesn’t recognize your network adapter.

This could be a mismatch of the configuration software that you used to set things up, or it could be the adapter only works on more modern versions of Windows than you have running. Check the box for the versions covered.

First, try to install the same adapter into another computer, perhaps with a more recent version of Windows on it. If it is recognized and works properly, you have at least narrowed down your problem to the first machine. Perhaps the version of Windows isn’t supported for that particular adapter. Or maybe the slot that you placed the adapter in is not working. (Not all slots on all computers are created equally, you should know.) Or there could be something else installed in that first computer that is preventing the adapter from working, such as a modem or a sound card that is interfering.

How do you know that Windows isn’t recognizing something? Go to Control Panel | System | Device Manager and look for your adapter with a small exclamation point in a yellow circle next to it. That means that Windows knows something about the adapter, but it isn’t completely installed. It may be set up wrong, or has a conflict with another device or some other problem. Double click on that device, look at its properties, and determine whether it is having a resource conflict with another device. If so, change one of the various settings on the device to parameters unused by the conflicting device. I know this is very general information, but a lot depends on the type of adapter you have and what else is in your system, and whether the adapter matches the particular slot where it is installed. To make any changes, look for the setup program on a disc that came with your adapter.

The lights on the back of your router don’t light up when you try to connect a cable in one of the ports.

Almost all routers include indicator lights that tell you when a computer is connected to one of the ports. One of your first clues when you turn on your computer is if this indicator light doesn’t come on, meaning one of several situations. The most likely one is that your cable is defective, or hasn’t been wired properly, or the connectors aren’t completely seated inside the adapter and router receptacles. Jiggle everything to make sure you have a solid connection.

One suggestion is to obtain a short length of Ethernet cable and bring your router next to your computer and see if you can connect them with this piece of Ethernet. If the light comes on, you know you have a bad cable and need to buy a new one.

Another possibility is that you are using the wrong kind of Ethernet cable. Of course, there are two different kinds, and you might have installed the “other” one. Without more expensive test tools this is difficult to track down. Again, purchase a new cable and that should do the trick.

Wireless network won’t connect

Setting up wireless networks with components from more than one vendor is possible, thanks to better implementations of the wireless standards. But it isn’t always easy. There are several things to consider, if you do intend to mix and match components from different vendors. Here are some pointers as you go about testing the various products:

First off, make sure that you have a working setup: try connecting an access point and a wireless adapter from the same vendor to make sure that both products function as intended.

Next, turn off any encryption. Wireless network products have implemented encryption in many different mechanisms, with multiple parameters to adjust to get it working properly. To increase your chances of getting things to work, turn off encryption at both the access point and in the wireless adapter settings. Once you get everything working, you can try to turn it back on for increased network security.

Understand that each network uses the same ID number, and make sure that you have specified these consistently and correctly among the access point and adapter settings. Different products call this ID number different things, such as an SSID, a Network Name, an ESS ID, or a Wireless LAN ID number. The trick is to find the right number (usually printed on the bottom of the access point) and type it in correctly (some products are case sensitive, to make matters even more difficult) in the right place in the configuration screen.

Keep things close together for testing. Don’t try to setup your wireless computer too far away from your access point: indeed, try setting them up initially side-by-side on the same desktop to facilitate the entire configuration. Otherwise, you may be running around your home with little to show for it.

Adjust the channel/frequency settings and transmission rates when in doubt. Most products allow you to specify one of the 11 radio channels that are used in these products. If you are having trouble communicating between access points and adapters, try to set them to the same frequency and see if you can get a signal. If not, then adjust the data transmission rate downwards: most products allow you to set this as well, and it could be that the products are too far apart to maintain a signal that can support the full 54 Mb/s.

Make sure you have the right network setting. Wireless network adapter cards can be setup in one of two modes: ad hoc or infrastructure. Ad hoc refers to peer-to-peer networks without any access points; infrastructure refers to networks that make use of access points. That seems obvious, but if you have chosen the wrong setting your network won’t work.

Finally, when in doubt, try to install the product on Windows XP. Older versions of Windows don’t have the best support for drivers for wireless networks.