found out to day why you cant copy sd card
Content Protection for Recordable Media (CPRM), the copyright protection technology used for the SD Memory Card, is key to enabling a new distribution system for music and other commercial media, because it assures a high level of protection against illegal copying. The technology was developed by 4C (The digital contents copyright protection technology licensing organization of IBM, Intel, Matsushita, and Toshiba.)
Having a proven record in DVD, this protection is enhanced in the SD Memory Card through the use of "key revocation" technology that is built into the card.
The card's control circuitry allows data to be read and written (in its protection area) only when appropriate external devices are detected. A check-out (copying) from a PC to the SD Memory Card is restricted to 3 copies in compliance with the SDMI specification. All SD-Audio products comply with SDMI.
The SD Memory Card copyright protection function has the following features:
Access to the SD Memory Card must be enabled by authentication between devices
A random number is generated each time there is mutual authentication and exchange of security information