Source Folder Set... button
Use this button to determine which folder contains the images to be translated.
Click the Source Folder Set... button, and the Select Source dialog appears.

To select the source folder:
1.
Locate the desired folder.
2.  Select it by clicking it once, or double click it (it will Open).
The Select "folder name" button now indicates the selected folder's name.
4.
Click the Select "folder name" button.
5.
The Translate Folder... dialog reappears.
The text next to the Source Folder Set... button now indicates the selected folder.  For example, Hard Disk:scans indicates all images contained in the scans folder, located on the disk named Hard Disk will be translated.

Note:  Any images contained in subfolders contained in the scans folder will also be translated.