[Help] Global.php RevCMS

Warning: require_once(C:\xampp\htdocs\app\interfaces\interface.core.php) [function.require-once]: failed to open stream: Permission denied in C:\xampp\htdocs\global.php on line 27

Fatal error: require_once() [function.require]: Failed opening required 'app/interfaces/interface.core.php' (include_path='.;C:\xampp\php\PEAR') in C:\xampp\htdocs\global.php on line 27
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