In some situations we have found that users who are dialling in to the company via a VPN tunnel from home and have a BT Router, lose the ability  to resolve DNS shortname whilst the IP address and FQDN still work.

This has been because of a feature that BT offer called “BT Web Address help”. What this does is if the internet has a problem finding the dns suffix of a system address the BT system tries to help. This will stop such things as the VPN tunnel using it’s configured DNS servers because the “BT Web Address Help” system kicks in before the VPN tunnel has a chance.

So what we have to do is to ‘Opt Out’ of the “BT Web Address help” system. This can be done by using the following link http://preferences.webaddresshelp.bt.com/selfcare on the system that is having the problem. Once you click on the ‘BT Web Address Help Preferences‘ link you will get the ability to ‘Disable’ the option.

Give the system around 30 minutes for the change to take effect and then try again. This time the shortname should resolve.