WP Shieldon is based on Shieldon library, a PHP library that provides anti-scraping and online session control for your WordPress sites.
When the users or robots are trying to view many your web pages at a short period of time, they will temporarily get banned. To get unbanned by solving Catpcha.
You can visit the plugin author - Terry L.'s blog, try reloading the pages several times then you will see how this plugin works.
/wp-content/plugins/wp-shieldondirectory, or install the plugin through the WordPress plugins screen directly.
Pluginsscreen in WordPress.
WP Shieldonmenu and complete all settings.
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