system.web.ui.page problem

hi friends . i write class name basepage and inheritance from web.ui.page


all of webpage in my project use basepage instead of web.ui.page
sometimes i click button in webpages and  buttons click don't work.i put breakpoint and look codes work
its stop in the basepage(after on pre init). also i use masterpage

class:
public class BasePage : System.Web.UI.Page
    {
        protected string XkullScilno
        {
            get { return Session["XkullBilgi"] != null ? ((KullaniciBilgileri)Session["XkullBilgi"]).sicilNo.Trim() : ""; }
            //set { ((KullaniciBilgileri)Session["XkullBilgi"]).sicilNo=value; }
        }
  & ...