You hear three beeps in quick succession. It wouldn't scan, and you can't read the barcode because part of it is obscured.

The label says "Pure Essential Oil, Orange, 1/2 ounce". We'll see if something like that is in the system. We want to initiate a product search, but first, we press the "Clear" key to get rid of the "input unknown" box.

Generally, if the system is given input that it cannot process, the alert box will display the faulty input if it is purely numeric, otherwise it will simply say "input unknown". One of the requested features for IS4C is to record failed scans and pass the information directly to the back end office.