Are you scanning barcodes from a stock item label? Sometimes barcode can be printed partially where some part of it is cut off. This can happen to long barcodes. Please make sure that barcode is correctly printed. If it is not, then try to change the size of a label or barcode variable where barcode is printed.
We use a number of internal barcodes based on the EAN-13 eg 5002502681515. Our scanner doesn't scan the barcodes printed from within Linnworks however, if we do the same barcode via the printer's own software the reader will scan it.
We are currently using Windows 10 (i5) and a Dymo Thermal Printer.
Would anyone be able to help with this problem please.