I've looked at the answers to this problem on the web and see that lots of people have the same problem with various answers none of which help much (should have come here first!)
Problem is Shockwave flash crash. New laptop -Google chrome - This has happened a few times
and I've uninstalled Shockwave Flash and reinstalled twice. Puzzled because this doesn't happen every time.
It also happens when I tried Firefox.
As ever thanks for your help
Isobel.S