Linux, FreeBSD, MacOSX: pear install http://pecl.php.net/get/xdebug Add to php.ini: zend_extension="/usr/local/php/modules/xdebug.so" Windows: Download Xdebug from http://xdebug.org Add to php.ini: zend_extension_ts="c:/usr/local/php/modules/xdebug.so"