Paypal problem

I’ve set-up my application as per instructions in htmlexec, protectebook, and paypal (pasted the appropriate code in the advanced window on paypal).
Everything seems to work properly… there’s a button to purchase the program on the nag screen.
When the user presses it it goes to a page where I’ve pasted the paypal form to buy the product.
The customer can buy the product and I get informed by paypal that the sale was made.
What’s missing, however, is protectebook does not return an email to the customer with the unlock code.
Just can’t see what I missed. Any suggestions from anyone??
-George Green

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