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> Use this file to discover available pages before exploring further.
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# Error: Duplicate reference for these products

When exporting products, you may see:

> Duplicate reference entry for product, Product ID: \[2/7, 2/8, 2/9, 2/10, …]

*(Export summary may also show* **_Duplicate reference_***.)*

The list uses product / combination IDs in the form `1/2`.

Each listed entry shares a reference already used elsewhere in the catalog (at least twice) — which is invalid for Cdiscount / Octopia.

Duplicate example:

![PrestaShop CDiscount duplicate reference example](https://storage.crisp.chat/users/helpdesk/website/-/3/f/a/8/3fa8ee645cd13200/prestashop-cdiscount-exemple-d_wc60tk.jpg)

Every product and every combination must have a **unique** reference:

[Validate your catalog structure](https://doc.common-services.com/en/article/validate-your-catalog-structure-cdiscount-1trq16m/)

Find a product by its ID in the catalog:

![PrestaShop CDiscount search by ID](https://storage.crisp.chat/users/helpdesk/website/-/3/f/a/8/3fa8ee645cd13200/prestashop-cdiscount-recherche_vopu1.jpg)