Mornington,
Glad to hear it's all going well.
I'm sure it is the answer, but still lies in the box until I pluck up sufficient courage to try again.
Strangely enough though, there has been no repitition of the problem since I uninstalled the canon on each devive and reinstalled with updated drivers. On the basis of 'if it ain't broke.......' maybe I'll leave it!!
Merry Christmas and happy printing!
mcdhu