During the development of a new access system based on modern RFID technologies it was found that companies producing access control systems for residential and office buildings still prefer the use of existing cheap solutions instead of incorporating new technologies. This is mainly due to the additional costs new systems require.The used legacy technologies are however prone to identity token cloning which allows easy access of unauthorized people to buildings. In previous paper, we have already briefly described a way how to detect cloned RFID tokens in 125 kHz RFID system.This paper lists the risks of the legacy access systems and offers ways how to detect a cloned 125 kHz tag, 13.56 MHz RFID MIFARE Classic card or Dallas Semiconductors iButton access token and how to pro-actively disable them.