Joomla 2.5.11 and K2 2.6.6

I am using for my site a Templaza Trekkingfan template which is fully compatible with K2. When installing this template from scratch the Comments form of a K2 Item shows only the Name, e-mail and the message. During development of my site I noticed that I have introduced somehow a different comment form (more like the standard K2 form which included standard the URL). I compared the template settings with my site settings but I could not find any difference. I also checked that the folder: \templates\tz_trekkingfan\html\com_k2\templates\default\item_comments_form.php is the original template php. This php disables the URL input among others. I am only using this templates , no template overrides.
It seems this php is not activated. Did I accidently modify a setting somewhere that introduces this behaviour. Any idea?

Is it possible for you to provide a link to the site?

www.saleshoptillyoudrop.nl/testmissbudget/

Hi MdeBoer, the only setting in K2 that I'm aware of that might affect it, would be in K2 parameters / Layout & Views / CSS & JavaScript Settings but it looks like it's getting the styles from your template.

Have you updated K2 lately or another plugin or module, and is it the same in all K2 Items ?

Hello MdeBoer,

Make sure the template developer does not use any frameworks or extensions that affect the default overriding procedure.

Peter, Krikor,

THank you fro your suggestions. I have checked impact of the upgrade of Joomla and K2 on the original template. THis works as expected. I am currently checking the plugins/components to see if this is the cause.

I will provide an update once this is completed.