First of all this is an awesome product. I've been looking for years for a free and simple file recovery program and this is the first.
In the drop down list of drives Recuva does not detect if you have inserted or removed a USB or any other type of drive while the program is open. If you attempt to scan a USB drive that is in the list after you have removed it, the program will crash.
Recuva v37
===========
System Info: MS Windows XP SP2, Intel Pentium M processor 2.26GHz, 2.0GB RAM, NVIDIA GeForce Go 7950 GTX
However, I think that this issue could be fixed a little more. If you select a removable disk in the selector and after that, at the same time, remove the disk and click at Scan button, the program will still crash.
I believe that would be needed to check, when click in the button, if the selected disk exists and, if is the case, generate an appropriate error message for such.