sd backup

Hi,

I'm trying to create a backup of my card (locked years ago).
I cloned CID to a new card and sector-by-sector cloned the contents of old card but it still complains "invalid sd card"..
Could somebody please tell me what am I doing wrong...? I thought that cloned CID and contents would be enough... How exactly does the car recognise that this is invalid card...? I've infotainment version 70.00.100