Community Rep Hvinire took to the forums to assure players that the pre-order site is up and running…. but it’s also being spammed like crazy right now, hence the error message. So, hang on and keep trying!
We’ve confirmed a high volume of traffic to the FFXIV Pre-Order Code Redemption website, which likely causes any errors you might have run into. If you receive an error while attempting to redeem your code, please wait and then try again later.
Our internal teams are working hard on this issue, and making every effort to relieve site congestion. As soon as we have any further information, we’ll be sure to update you all on our Twitter and through this forum.