Contextual Filters > Default option: PHP Code input option is missing I have two drupal 7 sites.  I'm able to select the PHP Code option to input a default value for a contextual filter on a view on Site A....on Site B I'm unable to find this option.  Is this a version issue or a settings issue?  I'm at a loss to find out how to retrieve this option.
Either the core 'PHP' module is disabled or you don't have the 'Use PHP for settings' permission.