The favourites are currently accessible from both partitions, but I was hoping to be able to point both IE's to just the one favourites folder so that which ever operating system I was using, I would always have the same set of favourites loaded up and whenever I added another favourite, it would be available to both IE's. In the same way that you can move the Temporary Internet Folder to a different location.
Thanks for that. I have also just discovered that Powertoys/TweakUI enables the location of the favourites folder (and many others) to be changed. So I've downloaded from Microsoft and it seems to have done the trick.