I have a markup for generating a list of clients and contacts info for each client. So, I am using nested list view control controls for displaying this. The outer listview control item template has a Image button, when clicked should open a popup extender so that I can attach new contacts to the client.
The problem is, in popup extender the target control id is set for the Image button above and I am getting a runtime error Unable to find the target control ID. Here is the markup...