Warning: require(ABSPATHWPINC/Text/Diff.php): failed to open stream: No such file or directory in E:\www\wp-includes\wp-diff.php on line 13

Fatal error: require(): Failed opening required 'ABSPATHWPINC/Text/Diff.php' (include_path='.;C:\php\pear') in E:\www\wp-includes\wp-diff.php on line 13