Hello I bet a lot of people come on here with HDCP errors, but I have been unable to figure out my issue through the information I have found online.
My device: Roku Streaming Stick (Purple) Connected Directly into TV HDMI peripheral which supports HDCP Running with a 1080px display setting
The Roku device was working smoothly with this set up just a few hours ago. I was watching Netflix when the remote stopped working in the middle of an episode. After a battery change, multiple restarts and failed pairing attempts (the remote would blink green as if waiting to pair but nothing actually happened), I tried a second remote, borrowed from somebody else's Roku. This remote seemed to be a newer version, lacked a light or connection button, and I could not figure out how to connect the two, so I eventually gave up and installed the Roku app on my phone. The remote had been chewed up by a dog so it seemed perfectly reasonable that there was some hardware issue with the remote. Either way, the Roku app worked, and with it I once again had control of my device.
Only this time, I received an HDCP Unauthorized: Content Disabled on a purple screen, within the Netflix viewer (the user interface for Netflix and Roku was working okay; it was only the video content that was blocked). I tried restarting the Roku, removing it and the TV from power, switching it to a different HDMI port on the television (that previously was working smoothly was an xbox one, so I know at least the HDMI part of the port works, though I don't know if xbox uses HDCP), and changing the display settings (to 720px and widescreen, neither of which fixed the problems). I noticed that when setting the display back to 1080px (our automatic) it took a relatively long time to confirm HDCP in the display settings screen, whereas the 720px confirmed almost instantly.
I am thinking maybe that the HDMI connection on the Roku is broken, might have been damaged when we unplugged it to attempt fixing the remote, and I might have to buy a new device, but I'd rather see what else I can try before it comes to that.
It's certainly possible the HDMI jack is damaged. Since your Stick is a 5 year old model, and the latest versions are significantly more powerful and improved, it might be time to just replace it. You might be surprised how much better a newer model works.
Dan Nvidia Shield, Roku Stick (3600), Ultra (4640), Premiere (3920), Insignia 720p Roku TV, Sharp 4K Roku TV, Windows 10 Pro x64 running Serviio and Plex on a wired Gigabit network.
It seems the HDMI output was damaged; on further inspection the CEC pin of the Roku's HDMI output was bent (the plastic that keeps it in place was broken off). I bent it back into place and am no longer getting the HDCP error.