To activate Disney Plus on a Blu-ray player, follow these simple steps. First, ensure your Blu-ray player is connected to the internet. Then, download the Disney Plus app from the player's app store if it's available. Once installed, launch the app and sign in using your Disney Plus credentials. An activation code will appear on the screen. Go to disneyplus.com/begin on a computer or mobile device, enter the activation code, and follow the prompts. Once the code is verified, your Blu-ray player will automatically activate Disney Plus, allowing you to stream your favorite shows and movies.