How do I deliver upgraded products to people who purchased the older item off marketplace?

[BohemianGypsy]

I have upgraded a product I sell on marketplace. I would like to give a complimentary upgrade of the new version to anyone who has purchased the older version. How do I do that? Thanks.

[Darren Scorpio]

Try using redelivery feature. Might be the only option

[Amethyst Jetaime]

If you have a list of your customers you can buy an update server and use that.  You product goes in the server and the list on a notecard or website, depending on what server you buy, and the server then sends it out to everyone on the list. Some also allow you to send a chat message and/or a notecard to explain to your customers why they are getting the product.