Backdoor communication failed - weevely 4.0.2

Warning: include(phar://shell2.php/x) [function.include]: failed to open stream: No such file or directory in /var/www/dvwa/hackable/uploads/shell2.php on line 1

Warning: include() [function.include]: Failed opening 'phar://shell2.php/x' for inclusion (include_path='.:/usr/share/php:/usr/share/pear') in /var/www/dvwa/hackable/uploads/shell2.php on line 1

why this error occur i can not modifiying the file shell2.php