Hi there, I've recently downloaded, activated and successfully used the WooCommerce PDF Invoices & Packing Slips plugin. However, I've just gone to view some invoices and I'm getting the HTTP ERROR 500 when it tries to open in a new window. This happens with both downloading and viewing the PDFs. Can you advise how I can resolve the issue please?
Many Thanks
https://wordpress.org/plugins/woocommerce-pdf-invoices-packing-slips/