Thanks rf065..... music to my ears!! I'm not sure what else was deleted (yet anyway) one of my worries ws that it came to light during a standard MB recall on the water pump electronics, when the update could not be completed because there was no communication with the AdBlue module. Anyway, I'm guessing here, the previous owner had AdBlue gremlins, and had the whole lot deleted. My main worry is that if the AdBlue module prevented communication to the lets say, the central computer, could it affect upgrading for other modules?