title: Angular Compiler Error (seems to be the wrong instance)
body: <p>when I try to run "ng serve" I run into the following issue:</p>
  
  <blockquote>
    <p>ERROR in ./src/main.ts
    Module build failed: Error: Angular Compiler was detected but it was an instance of the wrong class.
    This likely means you have several @ngtools/webpack packages installed. You can check this with <code>npm ls @ngtools/webpack</code>, and then remove the extra copies.</p>
  </blockquote>
  
  <p>Following this suggestion:</p>
  
  <blockquote>
    <p>$ npm ls @ngtools/webpack
    test@0.0.0 C:\Daten\Projects\test
     <code>-- @angular/cli@1.7.2
    </code>-- @ngtools/webpack@1.10.1</p>
  </blockquote>
  
  <p>So there are no multiple webpack versions installed. I tried to reinstall <code>@angular/cli</code> for multiple times....globally, locally, after using <code>npm cache clean -f</code> and <code>npm cache verify</code>. I did the same with <code>webpack</code>. Sadly there are not really many other people running into this issue, what makes it hard to solve. My google researches were not successfull due to all i could found was a chinese page translating that error into chinese and these two SO links (which do not provide a solution for me):</p>
  
  <p><a href="https://stackoverflow.com/search?q=Angular+Compiler+was+detected">https://stackoverflow.com/search?q=Angular+Compiler+was+detected</a></p>
  
  <p><a href="https://stackoverflow.com/questions/48774405/error-several-ngtools-webpack-packages-installed">Error: several @ngtools/webpack packages installed</a></p>
  
  <p><a href="https://stackoverflow.com/questions/47094987/share-node-modules-between-meteor-1-6-server-angular-cli-client-angular-mete">Share `node_modules` between Meteor 1.6 server &amp; Angular CLI client Angular-Meteor subprojects?</a></p>
  
  <p>my package.json:</p>
  
  <pre class="lang-js prettyprint-override"><code>"dependencies": {
      "@angular/animations": "^5.2.0",
      "@angular/common": "^5.2.0",
      "@angular/compiler": "^5.2.0",
      "@angular/core": "^5.2.0",
      "@angular/forms": "^5.2.0",
      "@angular/http": "^5.2.0",
      "@angular/platform-browser": "^5.2.0",
      "@angular/platform-browser-dynamic": "^5.2.0",
      "@angular/router": "^5.2.0",
      "core-js": "^2.4.1",
      "rxjs": "^5.5.6",
      "zone.js": "^0.8.19"
    },
    "devDependencies": {
      "@angular/cli": "^1.7.2",
      "@angular/compiler-cli": "^5.2.0",
      "@angular/language-service": "^5.2.0",
      "@types/jasmine": "~2.8.3",
      "@types/jasminewd2": "~2.0.2",
      "@types/node": "~6.0.60",
      "codelyzer": "^4.0.1",
      "jasmine-core": "~2.8.0",
      "jasmine-spec-reporter": "~4.2.1",
      "karma": "~2.0.0",
      "karma-chrome-launcher": "~2.2.0",
      "karma-coverage-istanbul-reporter": "^1.2.1",
      "karma-jasmine": "~1.1.0",
      "karma-jasmine-html-reporter": "^0.2.2",
      "protractor": "~5.1.2",
      "ts-node": "~4.1.0",
      "tslint": "~5.9.1",
      "typescript": "2.6.2"
    }
  }
  </code></pre>
  
  <p><strong>note:</strong> </p>
  
  <p>The project can be compiled at another PC - the only difference is the OS (he uses win7 while i use win10). </p>
  
  <p>greetings and have a nice week end,</p>
  
  <p>Messerbill</p>