I've just had one - very concerned gentleman about the errors that my computer was sending them.
He would be grateful if I would sit at my computer and he would then show me ....
Oh dear - I didn't have a control key at the bottom left hand corner of my keyboard - we did get confused about nomenclature
Eventually we sorted that out and then I was asked to press my Windows key - Ummm ?
Don't have one
After about 15 mins of this sort of thing I was able to tell him that I don't use Windows , never have and never will. Believe it or not he continued to insist that I was using Windows and my machine was sending him messages. Their information is absolutely accurate - I was told.

So he then asked what I was using - and was told a laptop

I think it eventually dawned on him that I really was not a Windows user .
He gave up
Now they are managing to spoof phone numbers - using 1471 I got 00118552348747 !
-------x-------x-------x-------x-------x-------x-------x-------x-------x-------x
If a thing ain't broke --- DON'T FIX IT
Experienced in making a mess of things

MacBook Pro on OSX 10.9 ,Virgin Super Hub , [ sssh - and a PC wired lappy using XP Pro ] all on
Virginmedia 60meg