IE & Firefox Cant browse to internet

Connected to the internet but cannot browse using firefox or internet explorer??A few day ago my user have a uniqe problems. Her Notebook cant browse to internet for unknow reason.I already try many way from re-instal the IE & Firefox, Reseting LAN configuration, confugure new Telkomnet instan setiing, disable Symantec Firewall & Anti virus but unfortunetly that still cant solve the problems.Then