Originally Posted by Aequitas
This is not entirely true most people think this but PayPal has told me that people buying intangable items online using PayPal are not covered for un-delivered products, I've had this happen lots in the past with assholes who get the product then take out a dispute against you to get there money back.
What you need to do is track everything, the payment amount, payment date, there IP address, once they click the download link re-log there IP address to know that they did download the product, save everything you can from PayPal.
Then when this happens take all that information and present it to paypal saying ok I sell intangible goods and this is what I do to proove that this person really did download and recieve the item they paid for then show them all the info and explain to them how it goes.
Most of the time PayPal will then side with you because the buyer is like umm what and doesn't know how to respond with all the evidence against them so PayPal sides with you.
If it gets too out of hand and its a smaller amount then save yourself the time and give them a re-fund.
But if this is something that is happening to you lots then try out this method.
Thanks for the advice. I'll try to track more info and see if that helps.