Error: Must specify "tsConfigPath" in the configuration of @ngtools/webpack

I am upgrading an old Angular project from version 4 to 5.

When I try to start my Angular 5.2.11 project I get an error that I don't have an tsConfigPath.

Error: Must specify "tsConfigPath" in the configuration of @ngtools/webpack. at AngularCompilerPlugin._setupOptions


I tried checking the path if its incorrect, but its correct.

This is in my webpack.dev.js

const { AngularCompilerPlugin } = require('@ngtools/webpack');
new AngularCompilerPlugin({
tsConfigPath: helpers.root('tsconfig.json'),
entryModule: helpers.root('src/app/app.module#AppModule')
}),

Continue reading...