Dodgy DNS in BT Home Hub 2.0

(C) Paul Downey

This is one of my problem and solution type posts for a nasty little problem I recently encountered with a BT Home Hub 2.0 and my Windows XP Pro x64 laptop that prevented me from successfully browsing the internet, despite having a working internet connection.

I don’t know the underlying reason for this problem, so can’t predict whether or not this will be useful to other people, but just in case it is, I’m detailing it here.

The Problem

I was unable to access the internet via the BT Home Hub 2.0′s wireless network with my laptop, however a different laptop worked fine. Unfortunately I didn’t have an ethernet cable to test the wired connection.

The DNS timeout error as seen in Firefox

I was able to connect to the network, however was unable to access the BT Home Hub following the instructions in the manual (by typing bthomehub.home into the address bar). In fact, whenever I tried to access any web page, the request would time out saying it was unable to connect. By watching the status bar in Firefox (my preferred browser), I could see that my browser was unable to complete a DNS lookup because all it said was “looking up www.google.co.uk”.

The Firefox status bar whilst performing a DNS lookup

(By the way, a DNS lookup is the process to convert a URL, like “http://www.google.com, into the IP address the computer needs to load the web page, such as 209.85.135.147 for Google.com)

Even stranger: Skype could connect and worked fine, however Windows Live Messenger couldn’t! If Skype worked ok, that meant I did have a working connection to the internet, but something else was wrong.

The Solution

I used the other laptop to access the BT Home Hub, and after fiddling around with the Home Hub to eliminate simple things like security causing problems, I put the two clues together:

1. Skype worked, showing I had a working internet connection.
2. My attempts to browse the internet failed because they couldn’t complete the DNS address look up

and added in the fact that, by default, computers will get DNS settings from the router (the BT Home Hub). I decided to try manually setting the DNS servers by copying the settings from the router. This solved the problem first time! Therefore, I believe the problem was that the BT Home Hub was failing to give my laptop the DNS settings it needed.

Unfortunately, because you’re bypassing the Home Hub, you won’t be able to connect to it by typing bthomehub.home into the address bar of your browser. If you can find out the IP address of your Home Hub, you could configure your computer to redirect that URL to the correct IP address (using the HOSTS file on Windows, for example) but I’m not going to go into that here.

Step-by-Step Fix

This step-by-step fix is for Windows XP, but should be broadly similar for other Windows versions. If the instructions don’t seem applicable to your computer, there’s always Google. (Specifically, these instructions were tested on a Windows XP Pro x64 SP2 machine)

The fix has two parts, first you need the settings for some DNS servers you can use, and then you need to configure your computer with those settings. In theory, you should be able to use any valid DNS server, but to avoid any complications I used the same servers as the Home Hub was configured to use.

Find your DNS Settings

To find your DNS settings on a BT Home Hub 2.0, using a computer that can connect to the internet without applying this fix/workaround and open your favourite web browser, then type bthomehub.home into the address bar.

This will open the BT Home Hub’s administration panel. Click on the “Settings” menu item:

Screenshot of the BT Home Hub Home Screen

Select “Advanced Settings” from the Basic Settings sub-menu:

Screenshot of the BT Home Hub basic settings screen

Accept the warning and continue to the Advanced Settings screen:

Screenshot of the BT Home Hub advanced settings dialog screen

Next, select “Broadband” from the Advanced Settings sub-menu:

Screenshot of the BT Home Hub advanced settings screen

Finally, write down the primary and alternate DNS settings:

Screenshot of BT Home Hub internet connection configuration screen

In my case, the Primary and Alternate DNS settings were 194.72.0.98 and 62.6.40.162 respectively, although yours may well be different depending on how BT manage their network.

Manually Configure Your DNS

First, open Network Connections by selecting the option in your Start Menu, or by opening the Control Panel and selecting the Network Connections options.

Screenshot showing the location of the Network Connections shortcut on the Windows XP Start Menu

Then right-click on your wireless adapter and open the “Wireless Network Connection Properties” dialog. Then find and select the “Internet Protocol (TCP/IP)” item, and click “Properties”.

Screenshot of the Wireless Network Connection Properties dialog window showing the Internet Connection (TCP/IP) item selected

In the Internet Protocol (TCP/IP) Properties dialog window, select the “Use the following DNS server addresses” and enter the preferred and alternate DNS settings you’ve obtained from the BT Home Hub. (Here’s a tip to make entering the settings easier: As you type, you can press space or type the full stop, ., to move to the next section of the DNS fields, and you can press tab to jump to the next field).

Screenshot of the Internet Connection (TCP/IP) Properties dialog window with manually configured DNS settings

Click “OK” in the Internet Connection (TCP/IP) Properties dialog window and “OK” again in the Wireless Network Connection Properties dialog window to save your changes.

Congratulations! You should now be able to browse the internet! (If the settings don’t take effect right away, try reconnecting to your BT Home Hub or rebooting your computer)