Hi, and thank you for your question. My name is ***** ***** I'll be assisting you today.
This has been an acknowledged compatibility glitch with Outlook 2016 and MAC OS X Sierra; to get around this issue, please do this now:
Click on the Apple menu button at the top-left corner of your screen, and then click "System Preferences".
Next, click "Network", and then select the network service you use in the list, for example, Ethernet or Wi-Fi.
Next, click "Advanced", and then click "Proxies".
Finally, UNCHECK both the "Auto Proxy Discovery" and the "Automatic Proxy Configuration" option, if checked. Click OK.
Done that, re-open Outlook - does it work all right this time?
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