To add HBO GO to your Roku, go the Roku Channel Store and add the HBO GO channel. Here's how: Press the Home button on your Roku remote. Select Streaming Channels > Search Channels. Enter HBO GO. On the channel info page, select Add channel. The first time you start HBO GO, you'll need to sign in to HBO GO.

HBO Max has more programming than the regular channel, a $15 monthly price tag -- and some confusion about why you can't watch on Roku or Amazon Fire TV. HBO Max, the HBO … HBO Go vs. HBO Now vs. HBO Max | Digital Trends Jun 13, 2020 HBO Max Inaccessible Via ROKU, HBO Go Members Confused

HBO Max app replaces both Now & Go apps. I would think the new HBO app on Roku would function the same way replacing both Go & Now logins. I'm not 100% sure, but it would make sense based on what happened with the HBO Now -> HBO Max update on other platforms.

HBO Go now available on Roku boxes, HBO subscription still Nov 04, 2011 HBO GO | Roku Guide

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Jun 13, 2020 HBO Max Inaccessible Via ROKU, HBO Go Members Confused Jun 22, 2020 3 Issues Keeping HBO Max and Peacock Off Roku and Fire TV Jul 14, 2020 Roku