I too haven't had any previous issues. The game launched for me yesterday, but today I'm getting this message in place of the launcher:

Unable to complete version check 30605 20448 10009 10019

I have done absolutely nothing at my end; no software updates/installs.

I've spent the past hour going through an older thread, http://forum.square-enix.com/ffxiv/threads/71773, however nothing suggested there has helped (I didn't bother with completely deleting the game and reinstalling it, lol)

What's disappointing is this appears to be an ongoing issue yet when I went to "Square Enix Support", there was no mention of this issue or a suggested fix. TBH, I just don't get it.. this appears to be a serious issue affecting a lot of players. Why not address it?