Thanks for your inquiry.
We understand that you are having an HDCP error when using your Roku Streaming Stick. We're here to help. To clarify, are you plugging the device into a Roku TV or non-Roku TV? Could you tell us how are you powering your Roku device? Is it connected to the USB port of the TV or to a wall outlet?
For additional troubleshooting steps to resolve the issue further, follow this link: What to do if you see an “HDCP Error Detected” message or a purple screen.
Let us know how it goes.