So I'm trying to add FFXIV as a Steam game now that's supported. The problem is that I need the product key, but can't find it anywhere. Got the game as a digital download.

Support topic says to look for Digital River, but I don't have the email anymore. When I type in my email and last five digits of the credit card, I get sent to the TERA online game page. Anyone have any ideas where I can find it?