ModalPopupExtender OK Button click event not firing?

Question

I have a Button inside an UpdatePanel. The button is being used as the OK button for a ModalPopupExtender. For some reason, the button click event is not firing. Any idea

Answer 1

Aspx

//Codebehind    
protected void OkButton_Clicked(object sender, EventArgs e)
    {

        modalPop.Hide();
        //Do something in codebehind
    }

And don't set the OK button as OkControlID.