Error 0 when creating normal portal with K2 categories

I've created a new K2 category and was going to use it on a News Show Pro GK4 module with normal portal, when I saved it I got the following error and I can't see my site. I disabled the module Show Pro GK5 module, I've deleted the category but I still have this error:
0
SQL=SELECT content.id AS ID, cats.name AS cat_name, cats.alias AS cat_alias, content.catid AS cat_id, users.name AS author, users.email AS author_email, users.id AS author_id, content_rating.rating_sum AS rating_sum, content_rating.rating_count AS rating_count FROM mkynr_k2_items AS content LEFT JOIN mkynr_k2_categories AS cats ON cats.id = content.catid LEFT JOIN mkynr_users AS users ON users.id = content.created_by LEFT JOIN mkynr_k2_rating AS content_rating ON content.id = content_rating.itemID WHERE ORDER BY content.created DESC

I can see that the WHERE clause is empty but I don't have a clue how to fix this.
I am using Joomla 3.1.5 and K2 2.6.8. I had Additional Categories installed as well but I disabled it.

Any help will be much appreciated.

Miry

Hello,

Did you selected non-empty categories as a data source?