You export your products and you get an error message like this one:
Incorrect code for the product XXX-YYY(1/2) - The EAN/UPC code (9999999) seems wrong. Product ignored.
Each product contains an EAN with an incorrect verification key, that means that the EAN code does not match the GS1 specifications or has not been issued by GS1.
Marketplaces require that EAN codes are only issued by the GS1 organization, the codes generated by other modules or software, lists that are sold or available for free on the Internet do not allow the export marketplaces.
Visit our blog about this subject :
http://blog.common-services.com/prestashop-codes-ean-places-marche/