Okay, one more place to check. Go to C:\Users\YOURUSERNAME\AppData\Local\UnrealEngine\4.7\Saved\
AppData folder is hidden by default, so you may need to either expose it or go directly there by using path above (with your user name).
There, move Config folder to desktop as before, and try again. You can get logs, too, while you’re in there; and attach that Logs folder and Config folder.