Waihekeans have been struck by phone scammers targeting, you guessed it, Windows.
Mac users are very smug about this, they got the phone calls too. Someone claiming to be from Microsoft has rung them warning of an urgent vulnerability in their (Windows) PC --- which is a bit of a giveaway really.
This is a classic social engineering attack - windows users are conditioned to think of their systems as being constantly under threat but otherwise out of their control. Thus they have to rely on outside experts doing obscure things to their computers. Once the scammers have taken you in, they get you to drop all your expensive security so they can install malware to your computer.
Microsoft are advising people who are taken in by these scammers to completely reinstall Windows.
Thing is, windows is the heart of the problem: why reinstall it?