Why does our open data site that is set to public in Open Data settings give a message that it is private when browsing to the URL?

Question

This the setting tab within the site manager

...and this is the message as displayed in IE 11 when browsing to the site URL: http://data-marc-gis.opendata.arcgis.com/.

Any thoughts/suggestions on what might cause this?

Mid-America_Regional_CouncilMA · Answer

Answered my own question: Make site public—ArcGIS Open Data | ArcGIS