I've had a couple of these calls... I ask LOTS of questions and they are adamant (and even agressive) about insisting that they are going to "help" me; when I asked "How do I know this isn't a scam?", they were smart enough to respond that it was good I was being careful. When I stopped playing along and told them I had a Mac... "click!"

However, here's a new -- and to me, extremely worrying -- twist: I was having problems with my phone line, so went to the BT website and reported a fault on my line ("intermittent dial tone").

A few days later, I had another call from these scammers, but they really had me going for a while, because they said they were responding to the problem I had reported to BT, and used the exact words I had used (i.e. "intermittent dial tone") when I had reported the fault to BT.

I did some checking to see whether I might have accidentally used a fake BT page to report my phone problem, but if that's the case, these guys have set up not just a page, but an entire website, which matches BT's in every particular.

I called BT and reported this to them, but the fellow I talked to seemed most concerned with reassuring me about the safety of my own line; he did not seem to get the point I was trying to make, which was that someone may somehow be accessing/intercepting information people submit to BT, and then using it to make their scam(s) more believable... [sigh!]

I find this very worrying indeed.