Black screen after launching the game

[HuaTuo]

I logged into the game just fine yesterday. Now, after downloading the 6.2 patch, after clicking on "play", game launches, expands to fullscreen, but the screen stays black. When I click mouse button while on the black screen, the game closes and I have to re-start launcher, put in login details again, rinse and repeat. Is this happening to anyone else?

EDIT: BEST TEMPORARY SOLUTION SO FAR THAT WORKS:

1. Launch the game through Steam
2. Log-in with your account details, but DO NOT press the Play button
3. While the launcher is on the screen where you can see the Play button, launch the Task Manager, and end the Steam process
4. After Steam has been forcibly closed, press Play
5. The game should work as normal

(big thanks to Purplebun)

EDIT: PERMANENT FIX SO FAR THAT WORKS:

Simply rename Steamclient64.dll in your STEAM installation folder to something else or remove it completely. Poof! - problem gone! We're not sure how that affect other applications but as far as FFXIV is concerned, no more black screen!

(thanks to Yate)