If after installing PaperPort, you later install a TWAIN device, you need to run INITWAIN.EXE to be able use that device with PaperPort.
Press this button to start your TWAIN device software. When you launch PaperPort, a TWAIN button will appear on the command bar. If you are already using a TWAIN device (such as a flatbed scanner or a digital camera), you can bring those images into PaperPort. Using PaperPort with a TWAIN scanner, digital camera, or other TWAIN device
