All of a sudden, the App is not working on either of our Roku's. The screen is stuck on initializing. We've tried deleting the app and reloading, with no success.
first, try a power down of your modem/gateway (unplug for 3+ minutes and then plug back in. after the LEDs show bootup complete try again.
This was happening to me on my Roku. I solved it by re-starting the Roku. Start with options (the gear symbol in the upper right corner of the screen), and look around until you see the re-start option. It only takes a minute or so to finish rebooting. There were some other apps that loaded but didn't log in, this fixed them all.
I'm not sure if this was the cause, but the problem began after a power surge in our house.