will failFLD-DPI-DESIGN-001^PW · offset 0 · label 1
This label was written for a 300 dpi printhead. On the 203 dpi printer selected, every dot coordinate covers a smaller distance — the label prints at 148% of its intended size and the barcode's X-dimension drops to 0.250 mm.
Rescale every coordinate, ^BY value and font height by 148, or send this label to a 300 dpi printer.
The 'it worked until we changed printers' class. 203 → 300 dpi is a 1.478× shift: content lands at about 68% of intended size. The address block still reads and the border still aligns, so it survives testing — and the barcode intermittently fails at the scanner gate.
will failBC-05^BY · offset 23 · label 1
The bar width is outside the GS1-128 range (0.495 mm to 0.940 mm, 0.495 mm target). At 203 dpi that means ^BY 4 or greater.
Raise ^BY to at least 4 at 203 dpi, or 6 at 300 dpi.
At 203 dpi ^BY2 — the power-up default — and ^BY3 both fail GS1.
will failBC-06^BC · offset 23 · label 1
This GS1-128 is shorter than the 31.75 mm GS1 requires. It may scan on a handheld and fail at a fixed scanner.
Set the height to at least 254 dots at 203 dpi, or 375 at 300 dpi.
will failFLD-C128C-ODD-001^BC · offset 23 · label 1
Subset C encodes digits in pairs. This payload has an odd number of digits, so the last one is dropped — the barcode prints, scans cleanly, and returns one digit short of the data underneath it.
Pad to an even digit count, switch to Subset B (>:), or let ZPL auto-select the subset.
Cloud Retailer help desk, "Zebra Label Missing Last Digit and/or Not Scanning All Digits in Barcode": odd-length codes such as EAN-13 lose the final digit — "subset C cannot process single digits, it MUST be in a pair." A customer-reported production failure, documented by a vendor.
will failGS-05^BC · offset 23 · label 1
This GS1-128 is missing the leading FNC1. Without it the symbol is a plain Code 128 and the scanner will not read the AIs.
Add FNC1 (>8) immediately after the subset start code, or use ^BC mode D.
will failBC-04^BC · offset 23 · label 1
Something is printed inside the barcode's quiet zone. The scanner cannot find the start of the symbol.
Move the neighbouring element away, or move the barcode.
Highest real-world scan-failure yield of any rule in this catalogue. Build the renderer for this one.
