Dammit, it took 5 mins of googling on the words
how to stop "text of the message"
and I found it
here. It works too.
But it will be interesting what M$ come up with in this case. I have noticed the receipt contains no contact info for the seller, except an email address. I've packed up the whole lot, receipts and all, and sent it off to M$.
Incidentally, this PC is built from parts (except laptops, I have never bought a ready made PC) so why not call it "OEM"? I could be selling it on to somebody like that.