Setup Always need update system files?

i have finish my program and i make setup for instalation but when i instaling in some system working with Windows XP it's Always giving message (your system files ar older than your setup files and it's need restart after update but when i try to setup again it's giving same message and till now i can't install my program
note i try to other system so some working ok and some giving same message
so what can i do to update system files correctly