Network Diagnostics: Using Windows Troubleshooter to Find Internet Connection Problems

how to configure a wireless routerIt’s frustrating when you can’t connect to the Internet. If you aren’t a techie person, you probably aren’t sure where to start troubleshooting. Luckily, Windows offers a “Network Diagnostics” tool that helps you figure out any network issues. While this doesn’t replace more low-level troubleshooting techniques, it helps the newbie find common issues that can be fixed with either configurations or hardware replacement.

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Accessing the Network Diagnostic Tools

This article assumes you have at least Windows 7, although Windows Vista and XP also have troubleshooting tools.

You have two options to access the network diagnostic tools. First, you should see a system tray icon that displays your network status. The following image shows you what this icon looks like on your system.


In the image above, the connection has no issues. When Windows detects that it can’t reach the Internet, a yellow exclamation point is shown over the image. If Windows can’t connect to the Internet or the local network, a red ex is shown over the image.

The type of issue you have (just Internet or Internet and local network) determines the steps you should take to troubleshoot. When you use the diagnostic tools, Windows will attempt to identify the type of issue and where the issue stems from.

If you see a broken connection icon in the Windows system tray, right-click the icon and select “Troubleshoot problems.” A window pops up and runs the diagnostic tool.

If no issues are found, the tool returns a window that asks you to further describe the problem. Otherwise, the diagnostic tool attempts to identify where the problem is stemming from. For basic networking problems, the issue might be from a bad cable or router. First, check that the cable between your computer and the router are connected. If you’re using wireless, click the system tray icon to browse wireless connections. Try to connect to your router again. It could be a simple change with the Wi-Fi’s password, so reconnecting will fix issues with changed passwords.

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If the problem is your router, first try to reboot the router. You probably have a personal or business router connected to the Internet Service Provider (ISP) router. Remember, if you reboot either one of these routers, all other computers on the network also lose connectivity. Therefore, you want to reboot shared hardware only after you let everyone know they will be down for a few minutes. Routers don’t take long to reboot, but you can tell people about 5 minutes of downtime for a reboot.

There should also be a hardwire between your personal router and the ISP router. Check that this connection is secure as well. Make sure you look at any hardwires for damage. Damage to the wires interfere with signals passed from your computer to the target website or shared network hardware. Replace any cable that looks damage to make sure it isn’t the cause of your connection issues.

If the problem is from a Windows configuration error, Windows will attempt to fix the problem. If you’re new to network connection issues, let the diagnostic tool run on your computer and let Windows fix any issues. Most issues are minor configuration problems that Windows can take care of.

If the diagnostic tool doesn’t work, the next step is to perform some analysis on the computer yourself. As long as the issue isn’t broken hardware, you can usually identify the problem without hauling your machine into the computer repair shop. One problem to note: if the issue is your ISP’s hardware, then you’ll need to call the ISP and have them repair the hardware. They will probably have you perform some steps to troubleshoot the issue on their end, but you can’t fix the ISP’s problems.

Manually Troubleshooting Your Network Connection Issues

It’s not difficult to manually troubleshoot issues, but some of the problems are intuitive. As you learn more about networking and computer hardware, you’ll get better at troubleshooting. Troubleshooting network problems requires step-by-step analysis.

If you know you have a good connection to the ISP router, the first step to take is to use the “ping” utility. Ping is available with any operating system. The ping utility sends a small packet to the intended target and verifies that you get a response. It helps you identify if you’re able to reach, for instance, a web host. If you can’t ping a host, then it could be a problem with your computer’s network card (either configurations or hardware), your router or even the host. Ping also helps you identify DNS problems.

Open the Windows command line utility. You can do this by clicking the Start menu button and typing “cmd” into the text box. Type the following command into the command line:

ping hostname

Replace “hostname” with any website you can think of. The best possible site to use is Google. You know the domain is probably not down and will give you a response. So, your command should look like the following:


The utility will send a message to the server four times.  If you receive a reply all four times, then you probably don’t have a raw connection issue. This means it could be your browser such as parental controls or filters. If ping works fine, try opening the website in a different browser.

Aside from hardware issues, the ping command also helps you troubleshoot DNS issues. When you run the command, you see a translation from the name to the IP address. If your DNS server has issues, you won’t be able to ping the host. Ping works in the same way your browser works. First, a host lookup is performed and the IP is what ping uses to contact the host. The translation is done on the DNS server. Therefore, if the server has any issues, ping can’t obtain the IP and the utility fails to communicate with the host (in this case, Google).

You can’t control your ISP’s DNS server, but you can still perform some kind of workaround. Sometimes, the ISP’s DNS server goes down and they configure a new DNS server in the interim. Since DNS servers are assigned when you boot your computer, reboot your computer and see if you get a new DNS server. You can check your DNS server by typing the following command into your Windows command line window:

ipconfig /all

In this view, you can not only view your DNS servers, but you can also identify another problem that could cause network connection issues. In the ipconfig utility, a list of network adaptors and corresponding IP and configurations are displayed.  Find the adaptor that you use to connect to the Internet. For most people, this is either a wireless or wired network card. If you use a VPN for work, you’ll need to identify your VPN adaptor.

Notice the IP address and DNS servers displayed. First, you should be able to ping the DNS server. If the DNS server is down, call your ISP or network administrator. Next, make sure you have an IP assigned. If you don’t have one assigned, you know that’s your issue. Finding the cause of that issue is another problem. First, it could be your DHCP server. DHCP servers dynamically assign IP addresses to your computer. With a personal home network, your router is typically the DHCP server. You’ll need to configure your router to send IP addresses to each client that connects to your network. You might need a little help from the router manufacturer’s instructions to configure the hardware.

Broken network cards or wires can also be the issue with a failed IP assignment. You can refresh your DHCP configuration. Sometimes, you change network hardware configurations and the old IP setup doesn’t automatically expire from your computer. You can force a refresh on your IP address using the ipconfig tool. Type the following command into the command line window:

ipconfig /renew

Your adaptor will refresh the IP address assigned using the DHCP server. Incidentally, this also happens when you reboot your computer, so a reboot will create a similar process. If you have damaged hardware, the “ipconfig /renew” command will fail.

Determine If Your ISP’s Network is the Cause

So how do you know if your ISP is causing the problem or your own network? You can identify an ISP network issue using the “tracert” command. This command traces the path from your home computer to the host. Using the same Google host as before, type the following command into the command line window:


Tracert works similarly to ping. Tracert sends a ping packet to each “hop” in the path from your computer to A reply is returned, so you know if the packet reached the hop and the hop returned a message. Some routers block ping packets, so you will see an asterisk in place of response time. This doesn’t always mean there is a problem, but it could indicate where the problem resides.

If a router goes down at a major ISP or backbone network, you’ll be able to reach some hosts but not others. Most large backbone networks such as Comcast or AT&T will reroute traffic. When a reroute occurs, you are still able to browse the whole Internet but your connection is a lot slower than normal.

Tracert helps you identify if your ISP has a router issue. If the packets come back up until a certain hop, you know that the ISP has an issue and you have to wait for them to repair the router or server before accessing the Internet.

Since you need ISP equipment to work with the Internet, you also have to check your ISP’s router. Whether it’s a home network or office network, you need equipment from a service provider. This also includes both cable and DSL connections.

While you usually don’t have full access to the ISP’s router, you can sometimes access the ISP’s router configurations using a cable and a laptop. If you don’t have a laptop, you need to connect to the router with a desktop or over wireless. For instance, AT&T wireless routers have a web-based interface that you can use to view settings on the router. You can identify if the router is connecting to AT&T’s network and if the router is obtaining an IP from the ISP’s network. If you think the ISP router could be the issue, you can always reboot it and see if that fixes the issue. It should be noted that you never want to reset the ISP router. Most routers come with a small button you can press and hold that resets the router to manufacturer settings. Since your ISP router is specifically configured to your ISP, it will ruin your setup.

A second computer helps you identify issues, because you can connect it to the network as well. If this second computer has no issues, then the problem likely lies with your main computer. If you know it’s not the hardware, try reinstalling the network card device drivers. Corrupted or deleted device drivers stop the hardware from running on your operating system, so you need to reinstall them to fix the problem. The Windows Network Diagnostic tool identifies device driver issues and will reinstall them if Windows is able to find the source files. However, if Windows doesn’t have a driver for your card, you need to reinstall the drivers from the disc included with the card. You can also download these drivers from the manufacturer’s site.

It’s not easy when you need to troubleshoot a Windows network on your own, but you can find the issue eventually with these tips. Troubleshooting also takes patience and the time needed to work through each issue step-by-step. While it doesn’t guarantee you’ll be able to fix the problem, knowing how to work with your network helps you identify the crux of the problem.

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