Hi, Recently I updated a site from Joomla 3.6.5 to 3.7.2 that uses K2 2.6.6
The problem that I have to solve is that in new or existing Menu items that the type is a K2 Category I cannot delete the selected category. And when I try to create a new one as I notice it doesn't create a working link.
It creates a link like this: index.php?option=com_k2&view=itemlist&layout=category
instead of this: index.php?option=com_k2&view=itemlist&layout=category&task=category&id=29
Could anyone please help me solve this ?

Thank you

Hello 2.6.6 is outdated, can you backup and install K2's latest version?

Hi Krikor and thanks for your reply.
I tried once to upgrade K2 but all pagination became a mess and I left it as it was.
The site has many customised files and I think this was the problem.
But with joomla 3.6.5 my client said taht K2 was working fine. Do you believe k2 2.6.6 could work with J.3.6.5 without problems.
At this moment I restore my backup of J3.6.5 to check if K2 was really working at this point. I know for sure that he had no problems adding items and new categories. But now it was the first time in the last year that he needed to create a new menu item and the problem occurs.
I will inform you later today.
Thanks.

Do you believe k2 2.6.6 could work with J.3.6.5 without problems.

That's so nice to hear :)

Let me know on your findings.

Hi again.
I completed the restoration.
Yes it works. I can create a new menu item typ with k2 category.
I can delete the category and change it an most important after saving the link is working fine.It is like this
" index.php?option=com_k2&view=itemlist&layout=category&task=category&id=29 "
In J.3.7.0 it doesn't get the id number of the category.
!!!

Have you altered any core files of K2 or only its templates?

I didn't build it from the start.
I support it 3 years so I don't know exactly all the changes. But I think that it is possible .
My client wanted many position changes.
See If you could check anything here is the webpage.
greekseashells.com
Try to click on these 2 links
greekseashells.com/index.php/gastropoda.html (category view)
greekseashells.com/index.php/gastropoda/patellogastropoda/patellidae/item/24-012-01-patella-caerulea-linnaeus-1758.html (item view)

Thanks

Could I try to update only some ccore files to see what will happen ?

Backup, backup and backup :)
You can update and reinstating the /templates folder (from your backup) and everything with frontend CSS/ JS

Hi Krikor.
I always have 2-3 backups. Ths is not a problem.
I try to find a solution, so this website be updated.
So, now I have J.3.7.2 with K2 2.6.6. You say that I should update k2 to the last version and then replace the /templates folder and all the css / js files that may have changed. Not only the css / js files that affect K2.

Actually let's take the long process

a) Read this getk2.org/documentation/tutorials/174-templating-with-k2-and-the-concepts-of-sub-templates

b) If you are using overrides chances are that all the edits will be kept once you update. If not override the template files you have edited.

c) Do the same for the modules.

Then you can update and see if the update was smooth.

Thanks Krikor.
I restore the site to J3.6.5 and my client will do some changes akd addings and when he will finish the job I will try to updated as you wrote.
I will post again when I will have some news.
By the way another client with J3.6.5 and K2 2.6.9 has exactly tha same problem but this website has no customisations. So I will try to update K2 there firstly.

Let me know if you are still having issues.