Issue including the wp-load.php file in your ajax.php file

On my local dev machine, I keep my plugins directory outside of my site’s default location so that they can be shared amongst other sites using sym-links. As a result your plugin had an error when trying to load wp-load.php in /sp-client-docuement-mangaer/ajax.php.

So I changed the line…

require( '../../../wp-load.php' );

…To…

$parse_uri = explode( 'wp-content', $_SERVER['SCRIPT_FILENAME'] );
require_once( $parse_uri[0] . 'wp-load.php' );

I made this change per this article http://frankiejarrett.com/the-simplest-way-to-require-include-wp-load-php/

https://wordpress.org/plugins/sp-client-document-manager/