My first suggestion would be to verify the game file through steam. You can use this tutorial if you don't know how. https://support.steampowered.com/kb_article.php?ref=2037-QEUH-3335. If that doesn't help I would try rolling back your driver to see if that was the cause of it. Lastly I would suggest deleting your local data files for Kings and Heroes. You can do this by going to your AppData folder under current user and delete the Archon folder in there. That should force reset some settings on your end and may allow you to finally load. The AppData folder is hidden by default, so you may need to go to your folder options on the computer and enable the show hidden files and folders option.