To establish a network (enabling the sharing of files, printers, and the internet) I connected a Belkin Wireless G router to my desktop computer (Windows XP Home Edition) using an Ethernet cable. All appeared to be working correctly, as the desktop computer could access the internet. Then I installed a Belkin 54g wireless card in my laptop (Windows XP Professional with SP2) and while the card appeared to be communicating with the router (indicated by very good to excellent signal strength) Internet Explorer would not load any web pages. I confirmed the correct WEP key is configured and, on the advice of Belkin technical support, disabled the Windows Firewall on both the desktop and laptop computers. Interestingly, the laptop could not successfully ping the router (192.168.2.1), yet the router configuration page could be loaded through IE on the laptop! Meanwhile, another laptop (with a built-in wireless card) has no problems connecting to the wireless router, and using the internet and email. From this experience I am pretty sure the problem is not the router, but is instead the laptop. To test this theory, I took my laptop to a friend who also has a wireless network. The wireless card found his network, but could also not access any websites through Internet Explorer.

You certainly followed a very disciplined procedure to troubleshoot the problem, so we will continue this approach. Since the problem does not occur when using another laptop on your network, together with the evidence that your laptop does not work correctly on another wireless network, it seems the issue is definitely the laptop as opposed to the router. Therefore, the problem could be attributed to either a fault in the wireless access card, or a problem with the laptop. So, we need to narrow down the problem to one of these possible causes. Firstly, remove/eject the wireless card from your laptop computer (so the computer does not attempt to use the wireless network during this experiment). Then, connect the laptop directly to the router using an Ethernet cable (just like your desktop computer is connected). Make sure the laptop successfully connects to the router, and then check it has been assigned an IP address. This can be checked by going to the ‘Start’ menu > ‘Run’ and type ‘cmd’ (without the quotes) and click OK. At the command prompt, type:
ipconfig /all
and press ENTER (note the space between ‘ipconfig’ and ‘/all’). This should display the IP address information for your wired Ethernet adapter. Assuming all is working, try accessing a web page through Internet Explorer.

Should you be able to access web pages successfully, it appears there is something wrong with the wireless card in the computer. In this case, your best option is contacting Belkin technical support for further advice. Alternatively, you could take the card back to the place of purchase and seek a replacement, since it is possible the card may be faulty.

On the other hand, should you still not be able to access web pages, there is something not right with either the Internet Explorer or networking configuration on your laptop. We will deal with the networking configuration on the laptop as our first check, since this is a more general fault. Disable any third-party security software on your computer (such as firewalls e.g. ZoneAlarm) and then try again. If this works, it appears the security software is causing the problem. Should this not resolve the issue, open a Command Prompt window and try pinging an internet site, such as ‘google.com’ using a command such as:
ping google.com
Check whether you receive a reply to this ping. If you do not, it seems no data is getting out from the computer to the internet. In this case, go to the ‘Start’ menu > ‘Control Panel’ and open the ‘Network Connections’ control panel (you may need to first select the ‘Network and Internet Connections’ category). Right-click on the Local Area Connection used to connect to the router, and select ‘Repair’. Once the connection is repaired, try again to see whether this has resolved the problem. If not, we next need to check the configuration settings for the LAN connection. In theory, this should not affect the connection since different settings are used for the wireless connection, so a misconfiguration in the wireless network settings should not affect the wired settings. However, it is still a worthwhile check. Right-click on the Local Area Connection and select ‘Properties’. In the window that appears, select ‘Internet Protocol (TCP/IP)’ and click ‘Properties’. Check the same settings on your desktop computer, and make sure both are configured in the same way.

Should the problem continue, try running the System File Checker in case any Windows files are missing or have become corrupted. Go to the ‘Start’ menu > ‘Run’ and type:
sfc /scannow
and press OK (note the space between ’sfc’ and ‘/scannow’). Once the SFC utility completes operation it will exit silently with no user feedback.

However, should you successfully be able to ping external addresses it seems the service being interrupted is the web. You can test this theory further by attempting to use another service, such as setting up an email account on your computer using Outlook Express. Assuming such other services work correctly, it seems the web is the problem service. Check the Internet Explorer configuration to ensure there are no options which could be stopping external traffic. In particular, make sure no proxy servers have been configured. This can be checked by opening Internet Explorer and go to the ‘Tools’ menu > ‘Internet Options’. Click the ‘Connections’ tab and the ‘LAN Setting’ button. Make sure the correct proxies (if any are needed at all) are configured.

All else failing, try downloading another web browser so see if that resolves the issue. My preferred web browser is Mozilla Firefox, a free open-source web browser available from: www.mozilla.org/firefox .