So you’ve added a pile of categories and products to your new store and then you notice the products-page slug in the breadcrumb trail and url.
Simple fix, right? Go in and edit the slug on the Products page. Back on the main site, clicking on a category results in a 404. Oops.
After hitting Google, there are a couple of old responses and the options aren’t in the same place. What should we try next?
The answer is remarkably simple. Under Settings > Store > General, toggle Use Hierarchical Product Category URL and Save Changes. You can then go back in, toggle it back and Save Changes again.
Links rebuilt and no more 404.