If you're using OS X El Capitan v10.11.5 or later, these updates include major new mac OS versions, like mac OS Sierra.
But the thing is, not everyone always wants to upgrade to a new firmware version.
Check for communication issues between i Tunes and Apple software update servers.
If you still see the error message, then continue reading to learn how to check your connectivity and security software.
In case, you don't want this auto-syncing, you can prevent it very much the way you do it on your i Phone or i Pad.
Turning off this feature would not only help you save some battery life on your watch but also stop it from being cluttered for space.