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We can enable Master Sync as follows:
This is one of the switches that you see on the phone's Home screen. The switch is with a group of switches: Wifi, Bluetooth, GPS, Sync, and Brightness. See photo below.
Another method to turn on Sync:
Go to Settings -> Data usage -> Go to the mobile tab. Press Menu button or 3dots button -> select Auto Sync data. This will enable Auto Sync.
When done, Email, calendar, contacts, and other Google services will be synced normally.
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