Hello & omg. I couldn't see how to reply to you. I created another question. Then now I see this, but don't know how I found it. Anyways, what did you do to get Spectrum to work on Roku? I uninstalled Spectrum, did Roku restart & added Spectrum again. It seems like Spectrum wants to start because I see channels then I get same error message. Thank you.
I had this error and it was resolved by updating the Roku software itself. The model I had this RLP-1031 error issue with is a stick, model 3600X. The upgrade required to get Spectrum app working again is 10.5.0 build 4167-24 as of 9/24/21. I update my Rokus on a timely basis, and this was the first time I've ever had the Spectrum app not work because the Roku's software wasn't the current version. I have 3 other models and all of those had no issues. On the 3600X stick, Spectrum app would start up and display the menus and channel numbers, but it would not stream anything. Before I thought to try updating the Roku itself, I'd already tried unplugging the power to it, restarting it, and clearing the cache, all to no avail. Note: I haven't deleted or reinstalled the Spectrum app in ages. I just needed to update to the latest Roku software for the 3600x stick. I didn't do anything with the Spectrum app itself.