We recently came across a problem with a users VPN connection – they could connect to VPN but when they tried to resolve any addresses on the corporate network side they resolved to an external IP address.
It turned out that the IP address in question was on the BT Broadband network.
It seems a number of other people have experienced similar problems:
A service called BT Web Help was getting in the way – any addresses that did not resolve were picked up by the BY DNS servers and a different address was returned. This address resolves to an advertising page from Yahoo and others.
This is similar functionality to OpenDNS – if an address does not resolve OpenDNS redirects you to a search page with sponsored links. That’s how OpenDNS get some money to keep their excellent free service up and running.
I don’t feel like helping BT to monetise DNS so I suggest you do the following to circumvent BT’s desire to interfere with your Internet connection:
1. Disable the web help function by visiting this page: http://preferences.webaddresshelp.bt.com/selfcare/preferences.cgi
Select Disable and Save.
2. Replace your BT router with a third party router – I always use Netgear (remember to keep your old BT router as, for some reason, they demand to have it connected when troubleshooting). The BT routers may be doing something odd to bounce the DNS connection back – I have not seen BT Web Help work when using a Netgear router set to use ISP supplied DNS servers.
3. Use a third party DNS service like OpenDNS – it’s free and you simply set the DNS entries on your router to OpenDNS servers to get going (they also provide a free filtering service if you so desire).