Vista and Blu-ray

Hi. Sorry if this has been raised before, but I only just got a new Notebook
with Vista Home Premium on board, so after years of familiarity with XP, I'm
now struggling to come to grips with the slightly different feel of the new
OS.

The question I have concerns playing a Blu-ray disc on the Notebook. It uses
an enhanced version of WinDVD to play HD discs, and there is no problem
watching on the Notebook's own screen. However, it comes with both SVHS and
HDMI ports/sockets, and it seemed reasonable to try playing back the Blu-ray
movie I had borrowed (as I haven't seen one before) on the main TV, 40-inch
screen and all that.

But the minute I plugged in the HDMI cable the movie stopped playing and
there was a brief note about the 'environment' being 'protected'. Obviously,
it makes no sense at all to be unable to play a DVD whether SD or HD through
the appropriate ports, so I had a little trawl round the internet today and
discovered that the problem might lie with Vista itself.

Can anyone here shed any light on this for me, please.

P