I have a question. Kind of an odd situation. I bought a D3 from a friend of mine that had it in his old car, bought a new one, and never came around to installing it. I bought it off him since I was buying a new car a few months later. He never gave me the DVDs for the maps and he moved out of the country. I got my car and I can't tell which version of the software is on the D3 now. Do I need the old disc to upgrade to this new version? If anyone can guide me I'd really appreciate it! I download .rar files corrupt a lot of the time so I want to be extra careful before trying this. I really don