I've just had a phone call from Microsoft support warning me that I have viruses on my computer, so I followed his instructions until he passed me over to someone else. I listened to him carefully. Eventually it got to the point where I had to access my internet connection and he told me to type "support.me" in the browser.
This was some 19 minutes after they started. It was at this point that I told him that I knew perfectly well that this was a scam, that there had been an article in the Guardian exposing them and that they were based in Calcutta. Strangely enough, the phone went dead. He realised that I had been conning them rather than the other way
The phone number appeared as 0212 777 3019 which is not a genuine number.
By the way, "support.me" would go to the Logmein site which is legitimate and is used by many support companies where they need to get access to customers' computers. What would have happened if I had typed "support.me" is that I would then be shown an authentic logmein screen and I would then have been told by the scammers to enter a number which if I had typed that in would then give them access to my computer.