If the WPS1500 omni scanner gets into a state where it will not scan any barcodes, here is a procedure to reset it.

This situation may occur when entering a certain interface mode, switching to inverse-only mode, or other.

1. Unplug the scanner's USB cable from the from the computer.
2. Press down on the button on the top of the scanner.
3. Keep the button pressed and plug the USB cable back into the computer.
4. The scanner will beep a few times.
5. After the beeps stop, release the button.
6. Unplug the scanner's USB cable from the from the computer again.
7. Wait about 5 seconds.
8. Plug the USB cable back into the computer (without holding the button).
9. The scanner should be back to the default scanning settings.