Excel 2013 is reporting "This image cannot be displayed" when I use the Camera tool?

Hi Folks,

This one has got me really stuck..... anyone had a similar issue or can suggest why this might be?

I want to use the Camera tool to link to cells as an image but the image that results simply says "This image cannot be displayed" ?

This used to work fine a couple of weeks ago so really stumped by why it should have stopped.

Thanks for any thoughts.