Well, if you live in Australia, and I can get my vehicle bought back then you would probably be able to do the same thing.
You will have to take the action against the dealer that sold you the car, not Mercedes. Unfortunately the issue is caused by Mercedes, but they are not taking any responsibility for this presently.
It affects all cars worldwide which have the COMAND system fitted, and has been prevented from working by Mercedes. How do I know this?? Mercedes have told me they have sun downed the software, and you can also find this answer through many other websites also.
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