title: React app fails to compile after installing 'node-sass'. How to fix "Module not found" error?
body: <p>I've built an react.js app which runs fine before installing 'node-sass' using npm install. 
  The app runs normally in the production build but fails to compile in development build, when using npm start.
  This problem doesn't occur with any other package except 'node-sass'</p>
  
  <p>The app worked fine when I imported it to another PC and installed 'node-sass' there.
  I tried reinstalling node and npm but to no avail.
  I've uninstalled node-sass globally too.</p>
  
  <p>This is my package.json:</p>
  
  <pre><code>  "name": "my_app_name",
    "version": "0.1.0",
    "private": true,
    "dependencies": {
      "gh-pages": "^2.1.1",
      "node-sass": "^4.12.0",
      "react": "^16.10.2",
      "react-dom": "^16.10.2",
      "react-scripts": "3.2.0"
    },
    "scripts": {
      "predeploy": "npm run build",
      "deploy": "npm run build &amp;&amp; gh-pages -d build",
      "start": "react-scripts start",
      "build": "react-scripts build",
      "test": "react-scripts test",
      "eject": "react-scripts eject"
    },
    "eslintConfig": {
      "extends": "react-app"
    },
    "browserslist": {
      "production": [
        "&gt;0.2%",
        "not dead",
        "not op_mini all"
      ],
      "development": [
        "last 1 chrome version",
        "last 1 firefox version",
        "last 1 safari version"
      ]
    }
  }
  </code></pre>
  
  <p>This is the error message i keep getting:</p>
  
  <pre><code>Failed to compile.
  
  ./node_modules/react-dev-utils/formatWebpackMessages.js
  Module not found: Can't resolve 'path\to\app\node_modules\babel-preset-react-app\node_modules\@babel\runtime/helpers/slicedToArray' in 'path\to\app\node_modules\react-dev-utils'
  
  </code></pre>