How to download macOS Sierra 10.12.3 public beta 1 to your MacmacOS Sierra, the next generation of Mac software, is now available as a public beta.
Update December 15, 2016: Apple has just released macOS Sierra 10.12.3 public beta 1 for members of the Beta Software Program. If you already have the macOS Sierra public beta installed, head to Mac App Store > Updates and download away. If you've been waiting for version 10.12.3 to get started with macOS testing, keep reading and we'll walk you through the set up!
Apple has been offering public betas for macOS for a couple of years now as a way for those interested in testing out the upcoming software on their Macs, and providing feedback. If that's you, you'll need to sign up, enroll your Mac, download macOS Sierra, and install it. It's not an overly complicated process, but we're here to walk you through it and, if you need it, a place to get extra help.
Apple occasionally offers updates to iOS 10, watchOS 3, tvOS 10, and macOS Sierra as closed developer previews or public betas for i...
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How to download macOS Sierra 10.12.3 public beta 1 to your Mac