Installation instructions: - Upload htmlpurifier.php to inc/plugins/ - Download the HTMLPurifier Library from http://htmlpurifier.org/ (use version 4.2.0 or newer) - Upload the HTMLPurifier library to inc/plugins/htmlpurifier/ (only the library/ folder, rename it to htmlpurifier/) - Create a directory cache/htmlpurifier and make it writable - Activate the plugin