I wonder if anyone can come up with a suggestion. I've only just set-up my E-Junkie account and am currently running on the week's trial - in case that makes any difference to the answer.
I've got a single PDF product set-up so far with, so far as I can tell, all the correct settings to make the PDF stamping work (by which I mean I've checked 'Send transaction data to a URL' and the URL I've put in the next page is http://www.e-junkie.com/ecom/oplug.php?ej_stamp_pdf=true&pdf_allow_copy=y&pdf_allow_print=y). Also, I've made sure that the three PayPal settings (as listed here http://www.e-junkie.com/ej/selling-with-paypal.htm) are correct.
I've also set myself up a discount code which gives me 100% discount.
Going through the webpage I've set-up, if I order the book and put in the 100% discount code click on the checkout button to through the "free checkout", I get asked for my name and email address, if I click on OK and then confirm my details are OK, there's a bit of a pause and then I get given the download link and sure enough the PDF is stamped as I wanted.
On the other hand, if I don't put the discount code in and instead checkout through PayPal, once I click on the "Complete Purchase" button, the download link page comes up immediately and the PDF I get doesn't have the stamp.
Does this suggest anything in particular that I'm doing wrong?