This is my first post in the forum. I'm starting right now in the J2ME and NFC world.
I've started playing with the Nokia 6131 NFC trying to save a contact information to a Mifare 1k, using the contact > options > transmit to tag. The contact is correctly saved in the mifare card, so it is read correctly by the phone.
The mifare card by default has keyA=FFFFFFFFFFFFFF and keyB=000000000000, and I can access it before write the contact (I can read the manufacturer data with no problem with an external card reader, sending the specific APDUs to it). After writing the contact I can not access the mifare.
It seems that the keys have been changed, so when I try to read any block in the card, a Authentication Error is returned.
Anyone can help me with that? If the keys are changed, which are these new keys?
Thank you very much in advance