Then I'll need to have a look at your output log (called player.log on Mac and Linux). This guide explains where to find it and recommends some sites to upload it to, since we can't attach files here on Steam.
https://steamcommunity.com/sharedfiles/filedetails/?id=463645931&searchtext=log
https://steamcommunity.com/sharedfiles/filedetails/?id=463645931&searchtext=log