category permalinks problem

I just attempted to update a site from 3.0.5 to 3.9.1 (this is the version of the site on my local server, not the live one)

The site has been live for 4 years & uses a custom permalink structure of /%category%/%postname%/ and a custom thematic child theme.

The wordpress installation is in a sub-directory of the public_html.

The main menu is basically categories, which then display all the posts of that category – the category also affects how the posts are displayed.

Now any categories just give a 404. I tried resetting the permalinks and was also able to confirm that rewrites are operating and .htaccess is writable.

Having read a number of forum posts from all the way back to WP 3.1 regarding this problem I decided to try another approach.

This should be repeatable by anyone.

I setup a brand new site and database, downloading the 3.9.1 code, and placing the code in a subdirectory – attaching to a brand new database.

Once the setup was complete, I created a category – portfolio.

I then created a post assigned to that category.
I then setup the permalinks to /%category%/%postname%/

The theme is the default 2014 site

Clicking on ‘portfolio’ results in 404.

So to recap –

1. fresh installed, unpopulated site.
2. Add category.
3. Add post in that category.
4. Click on category from the menu (site-side).

and you get a 404

If this issue has been around since 3.1, why hasn’t it been fixed?

This is the development site – however it is not always online.
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