many thanks, Spanners, I tried the DivX download and it works.
According to the info displayed while it was playing, it is a .avi file - that doesn't mean much to me, I must admit, but I seem to remember playing other such files without problems in the past.
Certainly Windows Media Player did go on about needing a new codec, Conan, but DivX mentioned codec in the blurb on the web-page and I really haven't the faintest what it is talking about!
As always, the combined wisdom of PPRuNe triumphs.
A happy GG