After a factory reset, I can't add channels. I can't reinstall them. I can't get the devices to update them and thus have nothing to watch. My online account listing says "Installed" when on both of them there is currently nothing there in the menus.
At the bottom of the page at: owner.roku.com do you see both units? Are they linked? Have you tried unlinking them and then relinking them?
That's about as far as I can go with this. Further instructions will have to come from someone knowing more than I do. We've traveled right out of my neighborhood.
I will make a note to myself and not try to do a system update with 300 channels installed.
Edit: It's all yours Basil. My shoe came untied some time ago.