Some remedies are about the SD card, but I don't have an SD card. Here is what I did:
- Navigate to Settings, Accounts, and Google.
- Move all of the toggles to “Off.”
- Navigate to Settings, Storage &USB.
- Tap “Cached Data” and then “OK.”
- Navigate to Settings, Application Manager, and then Downloads.
- Select “Downloads” and select “Force Stop.”
- Turn off your phone for a couple of minutes. Remove the battery if it's not sealed
- Switch your device on once more and wait until it has finished booting back up.
- Navigate to Settings, Accounts, and Google.
- Move all of the toggles to “On” to allow syncing again.