image not found or type unknown

Hello Jeroen,
How have you inserted this image? Is allow_url_fopen enabled on the server (you check the Status tab of the PDF Invoice settings for this)?
Documentation on this subject is here: https://docs.wpovernight.com/woocommerce-pdf-invoices-packing-slips/insert-images/

Ewout

Hi Ewout, thanks for your very quick reply!
so stupid I was checking the documentation of a plugin with almost the same title. In your documentation I found the insertion of images by means of the php. This is working!
thanks!!