I Have just used Recova and also had the same problem. Picutres were recovered, but when I tried with films, I got the message "device is not ready". I repeated the process several times with the same bad result, even closing and restarting the software. I checked that the origin and destination drives and they were active. Finally, I re-selected the origin drive on the top left of the screen (it was showing C: but orgin was E:), and it worked.!
Last night the process took hours; I had to leave it running overnight. This morning it took just a couple of minutes. Why???