Hi,
I've made a modal using ModalPopupExtender. The modal works normally until I set a asp:panel to visible = false (for c#) or display:null (for css) which causes the whole modal not to display at all.
So basically, it looks like
<parentPanel> some other stuff<childPanel Visible="False"> more stuff</childPanel></parentPanel>
The childPanel is only shown if the user meets a certain criteria which is checked for at codebehind