SD card not detect on Dk S7G2 board

i refer r11an0147eg0101-synergy-filex-port-block-fw-mod-guide reference program for sd card but there was some problem was't got available space and my program give me cannot get available space any one can please help me how can i solve this problem? i used DK S7G2 board.i used sandisk 8gb sd card and  format with fat32.