You need to give more information for us to be able to identify the problem.
Are you talking about HikaShop categories/images ?
If you turn on the debug mode of the joomla configuration and try again, do you get an error ?
Do you get an error in the javascript error console of your browser when you try to do it ?
Yes I am talking about HikaShop categories and images. When I used to click on the add button a window used to pop up and allow me to choose the category or image that I wanted. Now nothing happens when I click on the add button.
