Received this letter tonight. It was forwarded onto me from an address I haven’t lived in for over four years.
It’s a little scary to receive stuff like this as nobody wants their credit rating messed with. I’m still trying to work out a course of action (apart from phoning Talk Talk—previously Tiscali—in the morning) and hopefully doing this will be a good start.
It seems I’m not the only one receiving threats of this kind as you can read here, here and here.