Hello Marvin,

What other extensions are you using? Also please try reinstalling K2. I just tested 2.6.6 on a 3.1.1 Joomla! site in MAMP and it worked perfectly.

Hey,

thanks for your answer.

I have used Joomla and K2 with XAMPP and I got the failure...
Now I tested it on the webserver and it worked!

Regards

Alex

I have a big problem with that. Everything worked fine, but after updating the template, a fatal error.
Fatal error: Class 'K2HelperHTML' not found in /home2/alexhelp/public_html/holodprom.com/plugins/system/k2/k2.php on line 55

Support Re:
It's problem with order of K2 System plugin, please follow steps below to solve problem

1/ In your Joomla Administration access the Extensions>Plug-in Manager.
2/ Set the type to system
3/ Re-order the System-K2 to load higher then the System-JSN Framework

I'm going to fix your problem based in admin info that you gave it, but when I tried it, it's wrong.

Thank you,

Best regards,
Support Department.

For two days I can not solve the problem.
Help, who can?
holodprom.com/

Yes, you made your point clear with your avatar :) (just joking).

Which version of K2 are you using? If you updated your template you probably need to update K2 as well.
Since this is a template specific and related to JSN Framework, issue I am not able to assist you on this one. I am sure the template developers will assist you with your issue.

PS. Please backup before doing anything.