Warning: require(./source/class/class_core.php): failed to open stream: No such file or directory in C:\php\WWW\WWW\bbs\search.php on line 13

Fatal error: require(): Failed opening required './source/class/class_core.php' (include_path='.;C:\php\pear') in C:\php\WWW\WWW\bbs\search.php on line 13