Thanks, the .blend file is 11Mb and has produced a number of 2min avi files. So the materials and textures, smoke, views and movements are all working in the 3D viewport (screenshot)
However the output when saved (either during an animation/render run or manually e.g. ‘save image’) produces this

i.e. the red smoke goes AWOL
I sort of hope this is a silly e.g. a software switch or some output option, but I fear that this is a hardware issue caused by an upgrade of Blender and I don’t know how to proceed. Last year on the same computer with the same .blend I successfully created several 2min animation and put the output through a video editor to create a successful avi sequence(s) complete with smoke.
It’s a voluentary project/idea to create a sequence for my son’s school. It is a rotating sequence of the school badge.
Thanks in advance
Stuart