Barcode Mysteries Challenge: Bad and Worse

 In Barcode Quality Training

There are two kinds of barcode mysteries. Both are bad. one is worse.


One kind of bad barcode is the one that does not scan at all.

Like the crossword puzzle in the airline magazine, the answers are at the end. Can you figure it out without cheating?

Example A

Here is an example:



Hint: if you know Datamatrix symbol structure, it is obvious. No, the problem is not the defect in the bottom of the L track.




Here are two more barcodes that simply do not scan. Neither of these UPC symbols scan and they both have the same problem. Why? Hint: it is not because the check digit is wrong.

Example B

Example C


Barcodes that fail to scan are arguably the better problem to have. How can that be? The explanation makes a lot of sense if you think about it. A barcode that simply fails to scan is a problem you know about. Immediately. If you are going to have a barcode problem, that is the best kind of problem to have.


Even better if you do not have a barcode problem. We can help you detect them, fix them and prevent them to begin with.




Example D

This is the very worst kind of barcode problem. This barcode scans perfectly, but it has a problem—a devastating problem. Can you identify what that problem is?

Hint: You do not need access to the lookup database to discover the problem.

Scan it with your smartphone—the problem is obvious.


Example A has all the apparent attributes of a proper Datamatrix symbol–except for the square in the top-right of the clock track. That should always be a space or light-reflectance value. The presence of that dark square indicates that this is not an ECC200 compliant version of Datamatrix which is  virtually all currently-acceptable versions of Datamatrix. You may find a few in closed-loop applications but they will never appear in GS1, HIBC or other open-loop supply chains.

Example B and C share the same problem.

Version A UPC symbols encode 12 digits using two bars for each, that’s 24 bars. The left, center and right guard patters add two bars each–that’s a total of 30 bars.

Each of these UPC symbols are missing one bar on the right side.

How did this happen? A big and expensive mistake in pre-press. The printing looks perfect but these barcodes will never scan.

Example D is the worst problem you could ever have. It scans perfectly. That reassuring, comforting “beep” from the scanner fools you into thinking all is well. It is definitely not well and y u may not discover it until a lot of damage is done.

The readable characters under the barcode do not match the encoded data extracted from the barcode by the scanner. When this barcode was scanned in retail, the inventory was debited with the wrong product, over and over again. Then the supplier replenished the wrong item over and over and the popular item, the one the customer preferred and bought, was not replenished and disappeared from the shelf.

Got barcode problems? We can help you solve them and build them out of your process so they never recur. Contact us here.

We offer barcode quality training (online and on site), barcode testing services and process planning and control assistance.







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