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macOS and Windows
On macOS and Windows, find the ZeroTier app in your menu bar. Launch the ZeroTier One app bundle if it's not already running. Click the ⏁ icon on your menu bar and select Join Network.
On Windows, the ZeroTier one UI app lives in the system tray. Right click on the ZeroTier icon and select Join Network.
Additionally, with the macOS and Windows user interfaces, you can easily re-join networks that you've previously left.
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'Open Control Panel'. On the bottom of the control panel you'll see an area to join a network.
Type or paste in your network ID and hit 'Join Network'
From the Command Line
From the command line simply type zerotier-cli join ################ with ############### being the 16-digit network ID of the network you wish to join.
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