Warning: require_once(./include/common.inc.php) [function.require-once]: failed to open stream: No such file or directory in D:\Xampp\htdocs\forum\index.php on line 12

Fatal error: require_once() [function.require]: Failed opening required './include/common.inc.php' (include_path='.;D:\Xampp\php\PEAR') in D:\Xampp\htdocs\forum\index.php on line 12