Not finding channels on On-Demand

I just recently hooked my internet up to get use of the On-Demand feature of my HD-DVR box, and when I try and go to channels, for example DSC on demand by going to 1278 it just says the channel is not avaliable, or by going to HBO on-demand it says the same thing, is there a certain time period after hooking up the wired internet before the on demand channels present themselves as avaliable? or am I doing something wrong?

Thank you-