Daz Studio never fully loads

Hi,
starting today (2/17/18) Daz studio stopped fully loading, the preview window never initializes, and the program never truly crashes. it just never loads.
I'm running an nvidia 1060, and though recently I upgraded the driver to the 390 family, I just downgraded to 373.
I've uninstalled and reinstalled Daz studio, don't know what to do next!
Thanks!
Comments
Go to C:/Users/YOU/AppData/Roaming/Daz 3D/Studio4 and open the log.txt fiel, then look at the end - that should show roughly how far DS had got in booting up. (For Mac it's Application Support/Daz 3D/Studio 4 I think.)