I recently bought 2 copies of Defcon for my friends. Both are playing on MacOS Sierra, on early 2015 MacBooks. The game is crashing at launch for them. I'm on the same OS on a MacBook Pro mid 2014, and my own copy works fine. I asked my friend to open his steam file, and look for the authkey file to delete it, as is suggested on some forums. The file did not exist for him.
Please can you fix this.
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