Regard the Mini K2 module from Template Plazza, there on their website is a new version updated v.1.2 (Oct 2012 v.1.2 fixed helper.php to be compatible with K2 v.2.6.0) for K2 v2.6.0. Just download, install on top on the old one already installed and empty the cache if is enabled. It should work without any problem. Worked in my case.

@Tomy Francois + Joseph

This file is not used anymore. In the next release we are going to add an automatic removal of the file in the installation proccess.

If anyone still has this problem and is really annoyed by the error message there is a simple fix.
The problem occurs because of the line 360

K2Model::addIncludePath(JPATH_ADMINISTRATOR.DS.'components'.DS.'com_k2'.DS.'models');

in file plugins/system/k2/k2.php

you can replace it with the following,

require_once (JPATH_ADMINISTRATOR.DS.'components'.DS.'com_k2'.DS.'models'.DS.'item.php');
require_once (JPATH_ADMINISTRATOR.DS.'components'.DS.'com_k2'.DS.'models'.DS.'categories.php');
require_once (JPATH_ADMINISTRATOR.DS.'components'.DS.'com_k2'.DS.'models'.DS.'category.php');
require_once (JPATH_ADMINISTRATOR.DS.'components'.DS.'com_k2'.DS.'models'.DS.'comments.php');
require_once (JPATH_ADMINISTRATOR.DS.'components'.DS.'com_k2'.DS.'models'.DS.'cpanel.php');
require_once (JPATH_ADMINISTRATOR.DS.'components'.DS.'com_k2'.DS.'models'.DS.'extrafield.php');
require_once (JPATH_ADMINISTRATOR.DS.'components'.DS.'com_k2'.DS.'models'.DS.'extrafields.php');
require_once (JPATH_ADMINISTRATOR.DS.'components'.DS.'com_k2'.DS.'models'.DS.'items.php');
require_once (JPATH_ADMINISTRATOR.DS.'components'.DS.'com_k2'.DS.'models'.DS.'model.php');
require_once (JPATH_ADMINISTRATOR.DS.'components'.DS.'com_k2'.DS.'models'.DS.'settings.php');
require_once (JPATH_ADMINISTRATOR.DS.'components'.DS.'com_k2'.DS.'models'.DS.'tag.php');
require_once (JPATH_ADMINISTRATOR.DS.'components'.DS.'com_k2'.DS.'models'.DS.'tags.php');
require_once (JPATH_ADMINISTRATOR.DS.'components'.DS.'com_k2'.DS.'models'.DS.'user.php');
require_once (JPATH_ADMINISTRATOR.DS.'components'.DS.'com_k2'.DS.'models'.DS.'usergroup.php');
require_once (JPATH_ADMINISTRATOR.DS.'components'.DS.'com_k2'.DS.'models'.DS.'usergroups.php');
require_once (JPATH_ADMINISTRATOR.DS.'components'.DS.'com_k2'.DS.'models'.DS.'users.php');


basically instead of using the method addIncludePath to include the files in the model folder you call require_once for each file in the modle folder.

@chris

Using the API is the prefered method to load models. It's also much more shorter. I also think that is more easy for a non programmer to just remove a file than messing with code. Anyway we have already fixed that in the SVN version.

Hi Lefteris,

Sorry for the late reply.

Fatal error: Call to a member function categoriesTree() on a non-object in /home/.../public_html/sites/test/administrator/components/com_k2/views/items/view.html.php on line 124

Joomla 2.5.7
K2mart
K2 - Css4K2
PHP 5.3.17

After the update, the error occurs when the administration should be selected K2 articles.
Delete the file / administrator/components/com_k2/models/cpanel.php.
but the error persists. If you want to give access to the site.
Regards !!!

I did remove that file and the error message disappeared, but now it is not possible to order k2 items. The little blue arrows appear in grey and do not work.

¿Is that a bug or it has been removed on purpose?

Reinstalling version 2.5.7 everything works fine




Regards

Jose

Exactly same problem as Jose ^

Now I can't change item's order.

Hello removing your suggested file administrator/components/com_k2/models/cpanel.php. gets rid of the error message, but certain problems are continuing, such as using my Captify Content module - the assigned position for the module gives me the following error message instead of showing my images:

K2 is not installed! Error! Unable to retrieve any Images!

As far as I can see K2 appears to have installed, as I am able to add K2 content generally, so why am I getting the above error message?

Thanks in advance for your help.

@Jose @Eduardo Santos

The ordering function has not be changed. You just need to first sort by the Order column.

@jacob

You need to contact the developers of the module. Probably the will already have an update.

@Михаил Новак

When does the error occur? Are you using K2 2.6.1?