Thanks for the advice. I am sure now that it is a software fault with the Windows Camera app itself (the error message referred to a problem with the app). I now have the camera(s) working perfectly well with other, much better, apps which I have installed from the Store. I would have liked to get the Windows app working but I probably would not have used it now anyway, it is very basic and I found alternatives which are far superior. If I understand correctly, the Windows app is part of the Windows OS, it has no uninstall / reinstall option which I have used successfully with other apps from the Store if they malfunction.
clayto