This thread is resolved. Here is a description of the problem and solution.
Problem:
The user is unable to create categories when Toolset Types is active.
Solution:
The default post type "Posts" has categories deactivated, check this screenshot http://prntscr.com/vhy82l
I had to switch my user language to English as I am not comfortable with a Spanish user interface.
As you can see in this screenshot http://prntscr.com/vhy90m Categories are only activated for the custom post type "Fichas de empresas" and it is also available on its sub-menu.
This support ticket is created 4 years, 2 months ago. There's a good chance that you are reading advice that it now obsolete.
This is the technical support forum for Toolset - a suite of plugins for developing WordPress sites without writing PHP.
Everyone can read this forum, but only Toolset clients can post in it. Toolset support works 6 days per week, 19 hours per day.
I logged in to your site and found something strange.
I tried to add categories by going to Dashboard > Fichas de Empresas where the sub-menu should offer the link to manage categories (and tags) but those sub-menus are missing. They are also missing from the standard post type Posts.
When I went to Toolset > Tipos de entradas and edited the "Fichas de empresas" post type, where it shows the taxonomies that are assigned to the post type it showed etiquetas twice, that is instead of showing categorias it was showing etiquetas (checked), so there is something wrong here. (You can see the difference in the screenshots, one from your site, one from my site.)
The first thing I would do is disable Types (and the rest of the Toolset plugins).
Is it then possible to access the sub-menus for the standard Entradas post type, as shown in the 3rd screenshot from my site?
If not then there is something wrong with your site that has nothing to do with Toolset.
I would try disabling all other plugins and re-testing to see if you can identify the cause of this problem.
(Note, as an aside, I see that you have lots of Toolset plugins active on your site, several of which you almost certainly do not need, including Toolset Advanced Export, Toolset Framework Installer, Toolset Layouts, Toolset Module Manager, which you can almost certainly delete.)
I also logged into your website and I find out that the default post type "Posts" has categories deactivated, check this screenshot hidden link
I had to switch my user language to English as I am not comfortable with a Spanish user interface.
As you can see in this screenshot hidden link Categories are only activated for the custom post type "Fichas de empresas" and it is also available on its sub-menu.
I wonder if Nigel or I have missed something! If we did, please elaborate more on your request and explain what you would expect and what not working as expected.