I also use RCN but I have not checked to see if I can stream HBONow. I can get HBO (and other things such as HBOGo, Netflix, Hulu, Amazon Alexa, YouTube, and Prime, plus others). Now I seem to recall that I have to provide numbers that I have gotten when I subscribe. Maybe I never will know. I wonder if you call customer service you can demand someone that looks like a person that you download and send to them?