Hi, community edition? activate developer mode and activate full accounting future in user settings.

Hi,

As per the error message, it is raised when account_id is not set when creating the invoice line. So please make sure that the accounts are set for the product's/product categories.

Enable Full accounting:https://www.youtube.com/watch?v=sLetAnqo9m8

Thanks & Regards

in my case, my client was using Odoo 16, the thing was I had not set up the defaults for some things like Suspense Account, Outstanding Receipts, and Outstanding Payments

@Niyas Raphy & Mindaugas already did the enable full accounting but still error showing.

Thank you