Game stops responding on startup

When I click to play the game from Steam, the game opens, the mouse indicates the computer is working/thinking and nothing happens. If I clik on the screen, the black is overlayed with the usual white and a pop up comes up with "program is not responding". I think it might have started after the lastest update. Two weeks ago there was no problem when opening the game.

I did try to remove the mod folder, unsubscribe the mods and verify integrity of game files, but to no avail.