Lost channels

[halfrich]

Hi can anyone help a newbie!, I seemed to have lost loads of chanels on Fortec star hd reciever inc bbc hd I have re scanned the channels and the programs that do work recieve fine, when trying to access the bbc hd channel for example the sigal shows as good then goes to nothing and screen says no signal this is happening on lots of other channels loader is v1.5 thanks guys