I got mine to finally work, this is what I did. First uninstall or cancel the download for Dragon Age, then disconnect your internet both the wireless and the LAN cable. Once your xbox is offline and no trace of Dragon age can be found on it, Off your Xbox and remove thr power cable for about 30 seconds. Then put back the power cable and turn you xbox on. It should still be offline, put the Disc in and the download should start. Once the download is finished you need to update Dragon Age. For me, my modem setting were not compatible with the update so i used my iphones hotspot instead and it worked. the update went through and i can play now. i hope this helps you.
