They don't. These are cold calls and rely on suckers to bite
No, the first called definately knew that I'd sent an error report to Microsoft and refered to it several times. I tried to get rid of him by saying that I have a Mac (my laptop is a MacBook) but he said that the error report was sent from a PC with Windows.
I asked him where he was phoning from and he said 'Salt Lake City'. I assumed, at the time that he was phoning from the US but I've since discovered that Salt Lake City is an area of Kolkata.
Dave