title: Can't resolve 'ngx-bootstrap/component-loader/component-loader.factory'
body: <p>I'm getting this error when I tried <code>ng build --prod</code> with Angular 7.2.9</p>
  
  <pre><code>Module not found: Error: Can't resolve 'ngx-bootstrap/dropdown/bs-dropdown.config' in 'C:\Users\fvale\myproject\src\app'
  ERROR in ./src/app/app.module.ngfactory.js
  Module not found: Error: Can't resolve 'ngx-bootstrap/dropdown/bs-dropdown.module' in 'C:\Users\fvale\myproject\src\app'
  ERROR in ./src/app/app.module.ngfactory.js
  Module not found: Error: Can't resolve 'ngx-bootstrap/dropdown/bs-dropdown.state' in 'C:\Users\fvale\myproject\src\app'
  ERROR in ./src/app/app.module.ngfactory.js
  Module not found: Error: Can't resolve 'ngx-bootstrap/positioning/positioning.service' in 'C:\Users\fvale\myproject\src\app'
  </code></pre>
  
  <p>I don't have this error before I upgrade to Angular 7.x from Angular 6.x</p>
  
  <p>But! the weird thing is that I didn't even use ngx-bootstrap in my project, and I don't have it in my package.json. I installed it to check if that resolves the problem, but it doesn't do anything.</p>
  
  <p>Using: </p>
  
  <p>ngx-bootstrap: 3.2.0</p>
  
  <p>Angular: 7.2.9</p>
  
  <p>Bootstrap: 4.1.3</p>
  
  <p>and Angular CLI</p>
  
  <p>Package.json</p>
  
  <pre><code>{
    "name": "myproject",
    "version": "0.1.0",
    "license": "MIT",
    "scripts": {
      "ng": "ng",
      "prestart": "node version.js",
      "prebuild": "node version.js",
      "start": "ng serve --watch",
      "build": "ng build --prod",
      "test": "ng test",
      "lint": "ng lint",
      "e2e": "ng e2e"
    },
    "private": true,
    "dependencies": {
      "@agm/core": "^1.0.0-beta.5",
      "@angular/animations": "^7.2.9",
      "@angular/cdk": "^7.3.4",
      "@angular/common": "7.2.9",
      "@angular/compiler": "7.2.9",
      "@angular/core": "7.2.9",
      "@angular/forms": "7.2.9",
      "@angular/http": "7.2.9",
      "@angular/material": "^7.3.4",
      "@angular/platform-browser": "7.2.9",
      "@angular/platform-browser-dynamic": "7.2.9",
      "@angular/router": "7.2.9",
      "@fortawesome/fontawesome-svg-core": "^1.2.0",
      "@ng-bootstrap/ng-bootstrap": "^4.1.0",
      "@ngx-translate/core": "^11.0.1",
      "@ngx-translate/http-loader": "^4.0.0",
      "@toverux/ngx-sweetalert2": "^4.0.0",
      "bootstrap": "^4.1.3",
      "bootstrap-social": "^5.1.1",
      "core-js": "^2.4.1",
      "flag-icon-css": "^3.3.0",
      "font-awesome": "^4.7.0",
      "hammerjs": "^2.0.8",
      "moment": "^2.22.2",
      "ng2-color-picker": "^1.3.2",
      "ng2-slim-loading-bar": "^4.0.0",
      "ngx-bootstrap": "^3.2.0",
      "ngx-color": "^2.0.6",
      "ngx-embed-video": "^1.0.4",
      "ngx-moment": "^3.1.0",
      "ngx-slimscroll": "^7.1.0",
      "rxjs": "^6.4.0",
      "rxjs-compat": "^6.2.0",
      "simple-line-icons": "^2.4.1",
      "sweetalert2": "^8.3.0",
      "zone.js": "^0.8.29"
    },
    "devDependencies": {
      "@angular-devkit/build-angular": "^0.13.5",
      "@angular/cli": "7.3.5",
      "@angular/compiler-cli": "7.2.9",
      "@angular/language-service": "7.2.9",
      "@types/jasmine": "~3.3.9",
      "@types/jasminewd2": "~2.0.2",
      "@types/node": "~11.11.3",
      "codelyzer": "^5.0.0-beta.0",
      "fs-extra": "^7.0.0",
      "git-describe": "^4.0.3",
      "jasmine-core": "~3.3.0",
      "jasmine-spec-reporter": "~4.2.1",
      "karma": "^4.0.1",
      "karma-chrome-launcher": "~2.2.0",
      "karma-coverage-istanbul-reporter": "^2.0.5",
      "karma-jasmine": "~2.0.1",
      "karma-jasmine-html-reporter": "^1.4.0",
      "protractor": "^5.4.0",
      "ts-node": "~8.0.3",
      "tslint": "^5.9.1",
      "typescript": "3.2.4"
    }
  }
  </code></pre>