To sum up my fix. Checked my on-line google calendar settings to ensure mobile syncing was active. It was. On my Samsung S4 I uninstalled google calendar & re-installed a couple of times. Still kept receiving the syncing message. So I removed my google account & reconnected. That's when I received the message "The process android.process.acore has stopped". Based on users comments the best fix would be to reset to factory. Which I did and all is good except for losing SMS history

To sum up my fix:

I checked my online Google Calendar settings to ensure mobile syncing was active. It was. 

On my Samsung Galaxy S4, I uninstalled Google Calendar & re-installed it a couple of times. Still kept receiving the syncing message. 

So I removed my Google account & reconnected. That's when I received the message "The process android.process.acore has stopped". 

Based on users' comments, the best fix would be to reset to factory. Which I did and all is good except for losing SMS history