A JavaScript error occurred in the main process

Preflight Checklist

• I have read the contribution documentation for this project.
• I agree to follow the code of conduct that this project follows, as appropriate.
• I have searched the issue tracker for a bug that matches the one I want to file, without success.

Issue Details

• Electron Packager Version:
  • ^13.1.1
• Electron Version:
  • ^5.0.1
• Operating System:
  • macOS10.14.4
• Last Known Working Electron Packager version::
  • ^13.1.1

Expected Behavior

electron-packager ./build cra --platform=mas --arch=x64 --out ~/ --overwrite run cra.app

Actual Behavior

electron-packager ./build cra --platform=mas --arch=x64 --out ~/ --overwrite run cra.app A JavaScript error occurred in the main process Uncaught Exception: Error: Unable to find a valid app at Object.<anonymous> (/Users/Charlie/cra-mas-x64/cra.app/Contents/Resources/electron.asar/browser/init.js:120:9) at Module._compile (internal/modules/cjs/loader.js:808:30) at Object.Module._extensions..js (internal/modules/cjs/loader.js:820:10) at Module.load (internal/modules/cjs/loader.js:677:32) at tryModuleLoad (internal/modules/cjs/loader.js:609:12) at Function.Module._load (internal/modules/cjs/loader.js:601:3) at Function.Module.runMain (internal/modules/cjs/loader.js:873:10) at internal/main/run_main_module.js:21:11

To Reproduce

Additional Information

electron . is ok.but running error after the completion of the build

[dev-nicolaos]

I ran into this same issue. Make sure your build script is pointing at the folder where your package.json is.

For example I’d moved all my source code into a src folder. I’d been testing the app by running electron src and the app was running just fine. I installed electron packager and ran electron-packager src which successfully packaged the app, but when I tried to run the executable I got the above error message. Then I realized my package.json’s main field was already pointing at the src directory. I ran electron-packager . and it worked as expected.

[malept]

@Zyles please follow the instructions in https://github.com/electron/electron-packager/issues/992#issuecomment-491847998 - otherwise, there’s nothing for folks to use as a base to determine what the root cause is.