Recently, I came across the error below when attempting to open a large document library in Explorer View :

Some/SharePoint/Folder is not accessible.  You might not have permission to use this network resource. Contact that administrator of this server to find out if you have access permissions

Seeing as I am the administrator of the server, the site collection, the web application and the entire farm itself, I think I pass the permissions test.  It turns out that the real culprit has absolutely nothing to do permissions in any way.

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