[Sgt912]

I haven't used Calibre in a while and had a message to update the software, which I did.
When I last used it some time ago, I could connect both my wife's and my own Kindle Fires and it would show all of the books on the devices.
Now, when I attach the Kindle Fires, Calibre knows they're there and if I go into the configuration menu item, it shows the details of the devices - model and serial no. etc, so connection between laptop and Kindle Fires isn't a problem.
However, despite there being several books downloaded from Amazon to the devices and I can see them in the Kindles, they don't show up in Calibre.
When I look in the root directory of the devices, the 'Books' folder is there, but it's empty (hidden files should be shown, but there's just nothing there.
Have Amazon changed the way they store books on the devices or the locations of the books and/or is Calibre no longer able to access the storage location(s) of the (proper) Amazon books on the Kindle Fires?