The "format" is different, depending of the image that you use, so you have to be sure it's built for the image you loaded and that the image you flashed is supporting IPTV,

TS
_________________________
DM8000, DM800se, DM500HD, DM800HD, DM7025, DM7020s, DM7000, DM500s
VU+ Solo, VU+ Uno, VU+ Duo, Kathrein UFS910
Tivusat, TNTSat, Fransat, SSR/TSR, BBC1-2-3/ITV
DE-OpenBlackHole 1.4 image : http://www.openblackhole.com/