| I've just got a TT One, and had a similar problem this afternoon while attempting to install the free speed camera update.
I downloaded and installed the latest version of TT Home from the website, then followed the instructions on the yellow sticker. After I entered the code to activate the promotion, it just came back with a message "No updates available."
Tried entering the code again, but it came back with a message that it had already been activated.
Being an IT professional, it took me some time to spot that the TT One wasn't showing as a connected USB device on the PC, despite being connected and powered on as per the instructions on the sticker. Switched it off and on, and this time it displayed a screen asking if it should connect to the computer. Answered yes, and TT Home suddenly burst into life and displayed the speed camera and other updates ready to install.
Hope this helps! | 
