Konica Minolta bizhub C451 - Manual (Page 225)

Setting up the PostScript driver (Windows) 6
C451 6-30
8
Specify the storage location for the overlay file, enter the file name in
the “File Name” box, and then enter the overlay name or a comment in
the “Overlay Name” text box.
9
Click the [Save] button.
Instead of executing a print, the overlay file is saved and is added to
the list to be used for the next operation. The file extension is “.KFO”.