Writing [Password] to xDF2 - fails

Everytime I tried writing the [Password] datum to either my xDF2 or the MIFARE DESFire EV2 failed with the message, “Not valid NTAG21x”. Does anyone here know what might be this limitation ? Is password not a common field across all NXP chipset ? I understand that MIFARE DESFire EV2 has a unique organization of their App --> Files, Keys and Config structure. But, thought the password field is an overarching field at the top level of the fields hierarchy. What am I missing ? I bet I am - not sure what.


What app are you using?

“NXP Tools Pro” which renders above error and “MIFARE Writer” which says “Write Failed”

I don’t believe what you’re trying to do is possible, unfortunately.

Desfire uses encryption keys to control access to the data files on the chip.

The password you’re trying to apply is, to my memory, a NTAG thing.


This is accurate… and ultralight c admin functions, but those are under NDA (hilariously).

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