Steam windows .exe missing error?

[emz911]

The error I am getting when I try to launch the game from Steam on Windows:

Could not execute C:\Program Files (x86)\Steam\steamapps\common\xxx\lib\windows-i686\xxx.exe. Is it missing?

Notes:
- Launch only fails on the Windows system with .exe. I built the Steam game on a Mac and launching the app on Mac worked fine.
- Opening it directly from the Steam folder gives the same error.
- I looked at all forums discussing this problem, pretty sure this is not because of antivirus programs.
- The weird thing is that the error assumes the executable is within the "lib\windows-i686\" folder which it is not. In Steam installation I set the Windows launch path to simply "xxx.exe". If I put the exe in the windows folder, the error automatically adds another "lib\windows-i686\" to the path, making it "C:\Program Files (x86)\Steam\steamapps\common\xxx\lib\windows-i686\lib\windows-i686\xxx.exe". I'm guessing that the exe somehow has an attached path to the windows library folder?
- (PS: I replaced the game build distribution "lib" folder with the Steam Support Library Tom gave me, but kept the "python-2.7" folder, even though I tried both. I don't believe the problem has to do with the steam library but the directions aren't so clear, so I'm also worried that I made a mistake here.)

Would really appreciate any help! I rebuilt the game on Steam a dozen times, please help me

[emz911]

Can anyone with successful Steam windows upload experience talk about their process? :’( Don’t know what I did wrong, why does .app work but not .exe?

[emz911]

Nevermind I figured it out, thanks.