Help & troubleshooting for channels on your Roku device, including adding/removing channels, logging in to, authenticating, or activating a channel, channel-specific playback issues, assistance contacting channel publishers to report issues, and adjusting channel-specific settings.
I found a solution on a Playstation forum (should not matter that it's a Playstation). The resolution for people - and verified by others who had the same issue - was to change the network temporarily that you're trying to log into Netflix with. Connect the Roku to a different wifi network temporarily, sign into Netflix to get the UI-800-3 error out of the way. Then, go ahead and revert back to your normal network on the Roku.
Now yes, I totally understand that this might be easier said than done. But, can you create a hotspot with your phone, for example?
Here's the quote from the Playstation forum:
Well I have a fix for this if anyone has this problem.
I dont know why this works but it clearly bypasses what ever conflict is preventing netflix from connecting.
simply connect your ps4 to a different network and sign into netflix. For me I used my phone as a hotspot and connected to my mobile data. Once signed into netflix, sign out and set your wifi back up and reconnect ps4.
Bingo... you can now connect to netflix and no more bloody ui -800-3.
Hi, I'm having exactly the same issue i think it must be something to so with the 3, on the same network i have 2 roku sticks, an LT and a 2 all working fine. I connected my 3 via a hotspot on my phone and it worked but as soon as i connect back via ethernet i cant connect to netflix. I cant see it being a network issue otherwise why would everything else work ?? i even plugged the 3's ethernet cable into my blu ray player and that connected fine no problem. All other apps work on the three, amazon etc, just not netflix. I hope this is sorted soon as its driving me nuts!!!
I am having this issue on my roku premiere+ i have been trying to resolve it for over a week. Netflix is absolutely clueless. I was even told the signal was incompatible with my roku (bogus) i have download speeds at 113mbps. My older roku works fine as does my firestick xbox one S and my dish network reciever that has netflix. I have been dealing with them for over a week.... no luck.