Many thanks for your quick reply esmi. Absolutelly, I agree. This is not a WordPress message. But, somehow changing the permalink settings from “Default” to “PostName” has resulted in the site being “Access Denied” from certain PC’s, specifically PC in a corporate environment with strict(er) Web Filters.
So my question – is there a known fix so that changing the permalink settings does not result in sites being blocked in this way? Do you think this is still a host issue? Initial testing suggests the blocking is related to the .htaccess file, which I created as per the instructions in the WP Permalinks Settings page. If I rename the .htaccess I can see the site, but permalinks obviously stop working.