When use the Novastar system , showing that the sending card can’t be detected, how to solve?

Check whether DVI line and USB cable has been connected,the driver of graphics card has installed .if make sure all this no problem ,but still can’t detect sending card , then Try to change the DVI line and USB cable ;if still not work,maybe the USB driver didn’t install correct .re-install the software and tick off all the installation item, restart the computer after finish installation and open the software again.