Warning on Submit

Receive the following warning on submit

Warning: getimagesize(http://wp.spontaneous-insight.com/wp-content/uploads/2017/06/logo.gif): failed to open stream: HTTP request failed! in /home/spontaneous/www/wp-content/plugins/send-pdf-for-contact-form-7/classes/send-pdf.php on line 531

File does send appropriate, is received and has the logo in it.