If you bought it used, the seller probably lost the card because software on the card got corrupted and he removed it before he sold it because he didn't want to buy a new update. I would return it to the seller for an immediate refund. You will have to buy a SD card , give support the Serial number to run , wait several days to get any response with the register pass word and then likely be told the unit's free update period is expired and have to purchase an update for $600.When you can likely find a new left over clearance DS708 for about $850.