White Blank Page when Printing Packing Slips from Magento Admin

If you’re having trouble printing packing slips, receiving a white blank page when selecting Print Packingslips from the Actions menu in Magento’s Sales Orders page, then it’s likely you’re having the same issue I’ve had.

I found that having error_reporting enabled wasn’t enough

error_reporting(E_ALL | E_STRICT);

You’ll also need to add this to your index.php:

ini_set('display_errors', 1);

You’ll then be shown the following fatal error:

Fatal error: Declaration of Zend_Pdf_FileParserDataSource_File::__construct() must be compatible with Zend_Pdf_FileParserDataSource::__construct() in /home8/stonecr2/public_html/newsite/lib/Zend/Pdf/FileParserDataSource/File.php on line 41

The issue here is that the contructor of Zend_Pdf_FileParserDataSource_File requires a single paramter, $filePath, whereas its abstract class’s constructor does not. To resolve this, we need to make sure the abstract class matches its implementation, so make the following change

//from
abstract public function __construct();

//to
abstract public function __construct($filePath);

Test your printing, and you should be provided with a PDF file.