My computer is running Windows XP and I have been using Internet Explorer 6 to connect to the internet. Recently a message appeared advising that Windows updates were ready for installation. As it turns out, this updated the computer to Internet Explorer 7. However, following this update I was unable to access the internet using Internet Explorer 7. In order to restore internet connectivity I had to revert the computer to an earlier restore point, rolling-back to Internet Explorer 6. Thinking that it was a bit risky to rely on one web browser I installed Firefox. As I knew that Firefox adopted the Internet Explorer Connection Settings I ensured that “Automatically Detect Settings” was ticked in the Internet Explorer Connection Settings window. However, Firefox also could not connect to the internet and produced the following message “Unable to connect. Firefox can’t establish a connection to the server at www.google.com”. The computer connects to the internet through an iConnect 624W modem which is shared over domestic powerlines using Netcomm Homeplugs. Additionally, the affected computer has no third-party firewall software installed and only has the VET Antivirus software running. VET, Ad-Aware, and Spybot all indicate that the system is clean. How can I get other web browsers, apart from Internet Explorer 6, to work on the computer?

This is certainly an odd problem, as there appears to be something which occurs when you install the Internet Explorer 7 update which results in loss of internet access. Before proceeding further we need to conduct some checks to narrow down this problem as far as possible to the root cause. First, have you checked whether Firefox works correctly when your computer is not updated (i.e. still running Internet Explorer 6)? If Firefox works correctly in this pre-update instance then it seems that something in the process of the update to Internet Explorer 7 is breaking your internet access. However, should Firefox not work correctly then it seems something is awry even before beginning the update. In that case we will have a look at some of the Firefox settings to determine why this is not working. You mentioned in your question that Firefox adopts the Internet Explorer Connection Settings – this is not correct. Firefox maintains its own connection settings, separate from Windows. As such, we should check the Firefox settings. Open Firefox then go to the “Tools” menu > “Options”. Click the “Advanced” button and then the “Network” tab. Under the “Connection” heading click the “Settings” button. Unless your ISP has provided you with a specific proxy server to which you need to connect, or has given you other specific settings with regard to proxy servers, select the “No proxy” option then click OK and OK to save and close. The same should go for your Internet Explorer Connection Settings – unless you have been advised otherwise, leave all the proxy settings (including Automatically Detect Settings) disabled. This should be done otherwise each time you open Internet Explorer it will try to download a proxy settings file. Assuming that your ISP does not have such a settings file it will not be found, but Internet Explorer will keep trying to find the file for about 10 seconds before timing out (resulting in a 10 second delay between when you open the web browser and when you can use the internet). Disabling Automatically Detect Settings should prevent this issue from occurring.

Dealing with the second scenario, whereby Firefox works fine before updating to Internet Explorer 7, but ceases to work after the upgrade (together with Internet Explorer 7), this indicates a more general system problem. In this case it seems that something within the update is breaking your ability to access the internet through the web browser. However, we need to determine whether this problem is that your computer cannot access the internet at all, or whether the problem is limited simply to your web browsers being unable to access the internet. The easy way to test this theory is to try using a different program, which requires internet access, such as an email client or instant messaging client. If these work, it seems the problem is limited to your web browser. The first stage in diagnosing this issue would be to check the proxy server settings in both Internet Explorer and Firefox. Ensure these have not been incorrectly configured during the upgrade process. Should these be correct, and the problem still continues, our attention will now turn to possibility of some sort of corruption in the browser following the update. As a starting point, we will reset the browser to its factory default state. In Internet Explorer, go to the “Tools” menu > “Internet Options”. In the window that appears on the “General” tab under the “Browsing history” heading, click the “Delete” button. Click “Delete all” and then “Yes” in the confirmation window. Once this has completed, return to the main Internet Options window and click the “Advanced” tab. Near the bottom of the window click the “Reset” button. This will completely reset Internet Explorer to the default settings and disable all add-ons, thus allowing us to eliminate any misconfigurations or incompatible add-ons from being the cause of this problem. Once this has completed, restart Internet Explorer and check whether the problem continues. Should this resolve the problem, check to see whether Firefox still has the problem. If so, try clearing the Firefox cache by opening Firefox and then go to the “Tools” menu > “Clear Private Data” then tick all the options and click “Clear Private Data Now”. Once this has completed, restart Firefox to check whether the problem continues. If the problem is not resolved, you should try uninstalling Firefox and then download the latest copy from the Mozilla website (www.mozilla.com/firefox). Obviously you will need to download Firefox from a different computer, since this computer currently does not have access to the Mozilla website.

However, you might find that when you are testing other internet-enabled programs (such as email clients or instant messaging programs) that these also cannot access the internet. In this case, the signs indicate that the computer cannot access the internet at all, let alone the web. This is a greater problem, since the update appears to have broken networking on the computer. As such, we need to determine why your networking is no longer working. To start, we will check the network settings. Go to the “Start” menu > “Run” and type “cmd” (without the quotes) and click OK. At the command prompt window that appears, type the following command:
ipconfig
and then press the ENTER button. You should see the network information for all the network adapters on your computer appear. In particular, pay attention to the IP address. Make sure this address is not in the range of 169.XXX.XXX.XXX as this indicates a self-assigned IP address, and the computer is not properly connected to your home network. In this case, the problem appears related to Windows no longer connecting properly to the home network. However, should the IP address information look alright then we should next check whether there is a problem with DNS. This is the domain name system, which provides translation of friendly written address (e.g. www.google.com) into their numerical IP address equivalents (e.g. 64.233.167.99). To test whether DNS is the problem, open your web browser and type in the IP address for Google (http:// 64.233.167.99) rather than the friendly domain name address. If Google successfully loads, then the problem appears related to DNS and will need remedying. In any of these cases, they will require an entire explanation and further investigation in themselves. If you find yourself at this point then please contact me with the details for further advice.