It's just bad business to update "Viewer" with a pop up asking to update. The software should recognize that the key won't work with the update and warn the user.
Proper etiquette would be:
1) Tell the user that there is an update.
2) Tell the user that they will need to purchase the update if they proceed.
3) Tell the user all the new awesome features they will receive with the purchased update.
4) Double check ("Are you sure?") before the user clicks the update which will require a purchase.
5) Give the paying customer free 7 day trial licence (without making them jump through hoops) because they already have a previously paid license. (At least my trial started expired "0 days left" at the first minute).
6) Make the downgrade simpler than going to the web to download the old installer.
Hopefully you take some of these suggestions. I agree with people paying for upgrades and new licenses. I appreciate the 50% discount. It's the WAY that you went about it that was distasteful.
Thank you for listening!
