Hi Roberto
Sorry, we cannot replicate. Executing the following, correctly selects and acquires from the default device:
imageenview1.io.TwainParams.SelectedSource := imageenview1.io.TwainParams.GetDefaultSource();
imageenview1.io.Acquire();
I note that you are using two different TImageEnView objects (each has its own IO.TwainParams). I assume you are aware that setting "img.io.TwainParams.SelectedSource" does not change the selection of "preview.io.TwainParams.SelectedSource".
Nigel
Xequte Software
www.imageen.com