Barcode prints but will not scan
Troubleshoot why a printed barcode is not recognized by a scanner.
SCAN_NO_MATCH If a label prints but the scanner won’t read it, work through these in order.
1. Check print quality
Hold the label under good light. The bars should be solid black, sharp edges, no gaps.
Common print quality problems:
- Faded bars — printer head dirty or low on ink/thermal energy
- Missing rows — printer head needs cleaning
- Squished or stretched — wrong label size selected in Barcodeman
2. Check the quiet zone
Every barcode needs a blank margin on both ends (the quiet zone). If you see text or another graphic touching the bars, the scanner will fail.
Fix: in Label Designer, increase horizontal padding on the barcode element.
3. Check the symbology
- Code 128 — most reliable for short alphanumeric codes (recommended default)
- EAN-13 / UPC-A — for retail products with GTIN
- QR — good for phones, requires camera-based scanner
If you are using a handheld laser scanner, QR codes will not work. Switch to Code 128 or EAN-13.
4. Check the bar width
Minimum bar width depends on the scanner:
| Scanner type | Minimum bar width |
|---|---|
| Phone camera | 0.3 mm |
| Handheld laser | 0.2 mm |
| POS imager | 0.15 mm |
In Label Designer, click the barcode element → Properties → Bar width to adjust.
Still not working?
Export a 1:1 PNG of the label from Label Designer (right-click → Save as PNG) and try scanning it from your screen. If it scans on screen but not on paper, the issue is your printer. If it fails on screen too, the issue is the symbology or bar width.