Help getting started with Roku devices, including setup, connecting your device to your TV, linking a Roku device to your account at my.roku.com/link, adding channels, subscribing to services, and more.
Adding a new Roku to your current Roku account should go smoothly. Depending on how old your old Roku is the procedure may have changed from what you did before. During the setup you'll be asked to enter an email address. Make sure you use the same email address that your other Roku used. If you're not sure what it is, you can see it displayed under Settings->System->About on the old Roku. With any luck you'll receive an email from Roku with a link you have to follow to complete the linking process.
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