When a barcode won't scan: fixes at the counter

Beep. Nothing. Beep. Nothing. The customer waits while the cashier turns the can, tilts it, and finally types the number by hand. When a barcode won't scan, the cause is usually one of a handful of things: a dirty scanner window, glare, a damaged or poorly printed label, a code on a curved surface, or an item that isn't in your POS. Most can be fixed in seconds once you know where to look.

Knowing the order to check things saves a lot of frustration at the counter.

Is it the item or the scanner?

Start by narrowing it down.

Try scanning a different item that usually works. If that one fails too, the problem is likely the scanner, its cable, or its settings.

If other items scan fine, the problem is likely this one item: its label, its packaging, or its setup in the POS.

That single test points you in the right direction and keeps you from fiddling with the wrong thing.

What quick fixes work on the item?

Check the barcode itself.

Glare. Shiny packaging can reflect light back at the scanner. Tilt the item slightly so the light hits at an angle.

Curves. Barcodes on cans and bottles wrap around. Rotate the item so the barcode faces the scanner flat, or scan along the bars rather than across the curve.

Damage. A scratched, torn, wet, or wrinkled barcode may not read. Smooth it out or dry it. If it's badly damaged, look for a second barcode on the package.

Distance. Some scanners read best at a certain distance. Move the item closer or farther.

Faded labels. In-store labels printed on direct thermal paper can fade with heat and sunlight. Reprint them.

Small or low-quality printing. Some barcodes are printed too small or too light. If a product fails often, tell the supplier.

What quick fixes work on the scanner?

If several items fail, check the scanner.

Clean the scanner window with a soft, dry cloth. Smudges and dust cause a lot of failed scans.

Check the cable connection at both ends. A loose cable can make a scanner beep but not send data.

For wireless scanners, check the battery and that the scanner is paired to its base.

Restart the scanner by unplugging it and plugging it back in, or by turning it off and on.

Check for damage. A cracked window or a dropped scanner may need repair.

Wikipedia's page on the barcode reader explains how different scanner types read codes, which can help when troubleshooting.

What if the scanner reads it but the POS doesn't know the item?

Sometimes the scanner reads the barcode fine but the POS shows "item not found." That's an item file problem, not a scanning problem.

The item may be new and not entered yet.

The manufacturer may have changed the barcode, which happens when packaging changes.

The item may have been entered with a typo in the code.

Ring the item manually for now, then write it down. After the rush, add or fix the item in the POS. Checking the UPC printed under the barcode against what's in your system usually finds the mismatch quickly.

If you use NRS POS, ask how to add items and update barcodes. You can learn more at NRS POS.

What should the cashier do in the moment?

Keep the line moving.

Try two quick fixes: tilt or rotate the item, and try a second barcode on the package.

If that fails, type the number printed under the barcode.

If the item isn't in the system, ring it by department and price, if your store allows that, and note the item for a manager.

Don't spend more than a few seconds per item. Fix the cause after the rush.

How do you prevent repeat problems?

Keep a "won't scan" list at the register. Before closing, fix every item on it.

Clean scanner windows daily.

Check cables weekly for fraying.

Store label rolls away from heat.

Replace scanners that keep failing. For scanner cables and parts, browse the POS parts category on NRS Marketplace. For label rolls, check the paper rolls category.