Magento 1.7.02 Invoice Print Blank

Hello

I'm on PHP 5.4, Magento 1.7.02 as i want to print my invoice a go to a blank page.
A try following but didn't work :

- In FileParserDataSource, change abstract public function __construct(); to abstract public function __construct($filePath);
Didn't Work

Did you habe any Idea how i solve it ?

Thanks