do you have an original version of the game?
do you have the carpack installed??
and have you activated it with your original key of the original game?
if you do try to reinstall and go to C:\Documents and Settings\All Users\Application Data\Testdrive unlimited or where your aplication data is.
delete the addon.txt
and CDkey.txt
do not install the carpack yet.
first install and the game and then the patch
then start the game
enter your original CD key.
then try to connect
it worked for me.
For people who have the car pack.
if you have bought the original carpack
install it. then go to your mail where you have recieved your new carpack CDkey
this key do you need to use to activate your carpack
the game will ask you to
this will not work if you have a pirated version