Warning: require_once(includes/class.database.php) [function.require-once]: failed to open stream: No such file or directory in E:\Server_Data\Web Server\structure.php on line 2

Fatal error: require_once() [function.require]: Failed opening required 'includes/class.database.php' (include_path='.;\xampp\php\PEAR') in E:\Server_Data\Web Server\structure.php on line 2