Problem after Migrating from Prestashop 1.3 to Prestashop 8

[maniakpresta]

Hello.

We migrated from Prestashop 1.3 to Prestashop 8.

We discovered that we cannot manage the add or edit of categories to products.

What we saw is that in the 1.3 database, category 1 is (HOME) and (root).

In the Prestashop 8 database, category 2 is (HOME) and (root).

In the database of 8 after the migrate, category 1 is (root) and category 2 is (HOME)

Also, category 1 has id_parent (582), a category created during migration that did not exist in 1.3 and is not processed in the Prestashop back end (The object cannot be loaded (or found).

First of all, I would like to ask if it is possible to migrate from Prestashop 1.3 to 8 and if there is a solution to the above problem.

Thank you.

 

[ComGrafPL]

I did one time 1.3 but to 1.7 and 1.4 to 8. With some issues. Regarding categories. They are working on new products? Issues are only on migrated ones?

[maniakpresta]

24 minutes ago, ComGrafPL said:

I did one time 1.3 but to 1.7 and 1.4 to 8. With some issues. Regarding categories. They are working on new products? Issues are only on migrated ones?

The problem also exists in the new products we add.

[ComGrafPL]

Is it edition version? re do the categories?

[musicmaster]

The new category is "root". It comes below your Home category. It was introduced in version 1.5 together with multi-shop. As it is created during the update to 1.5 it will have a high id number.

Your category tree problems signal some problem with the nleft and nright fields.

You could try my free Prestools. It has an Integrity Checks function that includes an option to regenerated this tree.

I made some upgrade tools (Copy_shopdata and UpgradeHub ) but they won't go further back than 1.4.9 at the moment.

[Reha Ultimate]

In PrestaShop 1.5+ the category structure was changed, and the system expects:

ID 1 = Root

ID 2 = Home

When a shop is migrated from very old versions (like 1.3), these IDs often remain reversed. As a result, the Back Office cannot correctly load or attach categories to products.

In your migrated database the structure is incorrect:

Category 1 is not Root

Category 2 is not Home

Category 1 even has an invalid parent (ID 582)

This breaks the nested-set structure (nleft / nright) and causes exactly the issue you describe.

The fix is:

Set category ID 1 to be the real Root category:

id_parent = 0

Correct values for nleft, nright, level_depth

Set category ID 2 to be the Home category, with:

id_parent = 1

Make sure all other categories connect under this tree properly.

Regenerate the category nested set (nleft / nright) after correcting IDs.
Prestools or the built-in Category::regenerateEntireNtree() can rebuild the tree.

Once Root is ID 1 and Home is ID 2—as PrestaShop 8 requires—the product category selector will work normally again.

[musicmaster]

10 hours ago, Reha Ultimate said:

In PrestaShop 1.5+ the category structure was changed, and the system expects:

ID 1 = Root

ID 2 = Home

When a shop is migrated from very old versions (like 1.3), these IDs often remain reversed. As a result, the Back Office cannot correctly load or attach categories to products.

In your migrated database the structure is incorrect:

Category 1 is not Root

Category 2 is not Home

Category 1 even has an invalid parent (ID 582)

This breaks the nested-set structure (nleft / nright) and causes exactly the issue you describe.

The fix is:

Set category ID 1 to be the real Root category:

id_parent = 0

Correct values for nleft, nright, level_depth

Set category ID 2 to be the Home category, with:

id_parent = 1

Make sure all other categories connect under this tree properly.

Regenerate the category nested set (nleft / nright) after correcting IDs.
Prestools or the built-in Category::regenerateEntireNtree() can rebuild the tree.

Once Root is ID 1 and Home is ID 2—as PrestaShop 8 requires—the product category selector will work normally again.

That is not correct.

When you upgrade from 1.4 to 1.5 it will create a new category with the name "root" and that category will get the next available id number.

[Reha Ultimate]

On 12/10/2025 at 11:59 PM, musicmaster said:

That is not correct.

When you upgrade from 1.4 to 1.5 it will create a new category with the name "root" and that category will get the next available id number.

 My friend, it is Prestashop 1.3 to Prestashop 8 migration, not to 1.5

[musicmaster]

6 hours ago, Reha Ultimate said:

 My friend, it is Prestashop 1.3 to Prestashop 8 migration, not to 1.5

Prestashop's autoupgrade module works step by step, processing sql files that list what must be changed in the database for the next version. And at some point during that process it will cross the 1.4-1.5 border and add the root category. 

Those files are found in the /install/upgrade/sql directory (up to 1.7.0) and /modules/autoupgrade/upgrade/sql (after 1.7)

Of course third party tools can choose to work in another way.