When activating Shipper Plugin it throws Fatal Error

I installed Shipper pro. When I attempt to activate it, an error is thrown:

Warning: file() [function.file]: Filename cannot be empty in /wp-content/plugins/shipper/lib/functions.php on line 21

Fatal error: Class name must be a valid object or a string /wp-content/plugins/shipper/lib/shipper/helper/class-singleton.php on line 44

  • Prathamesh Palve
    • Staff

    Hello Marcus,

    I see that the PHP version at the moment is 5.2.17, which is too old. Although PHP 5.6 is the new minimum required version for running WordPress, the project’s technical requirements page recommends users ask their hosts for PHP version 7.3 or greater.

    While checking on my end I have seen that Shipper worked great with the minimum PHP WordPress requirement that is 5.6. I’m afraid you will have to back up your site and then plan a PHP upgrade soon.

    New PHP versions come with improved speeds, stability and a huge number of security patches with it. Kindly upgrade your site to minimum PHP 5.6 version and then try to activate and run shipper on your end.

    If you have any doubts or need any help updating the PHP version and shipper, feel free to reply in the thread here and we would be very happy to help you with it.



  • Dimitris
    • Support Star

    Hello there Marcus

    I’m afraid that PHP v.5.6 is the minimum requirement for Shipper currently and in order to provide compatibility for older PHP versions (if even possible) it’d require some extended re-writing in Shipper’s codebase.

    Warm regards,


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