Ailsa Ailsa - 1 year ago 316
React JSX Question

"module not found : Error: Cannot resolve module 'react/lib/ReactMount' "

I used Reactjs and webpack to start a project, and when I run the "node server" in the command prompt, there is an error like this:

enter image description here

And the chrome explorer opened successful but also have problems as follows:

enter image description here

The github is: (

Here is the package.json

"private": true,
"version": "0.0.1",
"description": "YOUR DESCRIPTION - Generated by generator-react-webpack",
"main": "",
"scripts": {
"clean": "rimraf dist/*",
"copy": "copyfiles -f ./src/index.html ./src/favicon.ico ./dist",
"dist": "npm run copy & webpack --env=dist",
"lint": "eslint ./src",
"posttest": "npm run lint",
"release:major": "npm version major && npm publish && git push --follow-tags",
"release:minor": "npm version minor && npm publish && git push --follow-tags",
"release:patch": "npm version patch && npm publish && git push --follow-tags",
"serve": "node server.js --env=dev",
"serve:dist": "node server.js --env=dist",
"start": "node server.js --env=dev",
"test": "karma start",
"test:watch": "karma start --autoWatch=true --singleRun=false"
"repository": "",
"keywords": [],
"author": "Your name here",
"devDependencies": {
"babel-core": "^6.0.0",
"babel-eslint": "^6.0.0",
"babel-loader": "^6.0.0",
"babel-polyfill": "^6.3.14",
"babel-preset-es2015": "^6.0.15",
"babel-preset-react": "^6.0.15",
"babel-preset-stage-0": "^6.5.0",
"bower-webpack-plugin": "^0.1.9",
"chai": "^3.2.0",
"copyfiles": "^1.0.0",
"css-loader": "^0.23.0",
"eslint": "^3.0.0",
"eslint-loader": "^1.0.0",
"eslint-plugin-react": "^6.0.0",
"file-loader": "^0.9.0",
"glob": "^7.0.0",
"isparta-instrumenter-loader": "^1.0.0",
"karma": "^1.0.0",
"karma-chai": "^0.1.0",
"karma-coverage": "^1.0.0",
"karma-mocha": "^1.0.0",
"karma-mocha-reporter": "^2.0.0",
"karma-phantomjs-launcher": "^1.0.0",
"karma-sourcemap-loader": "^0.3.5",
"karma-webpack": "^1.7.0",
"minimist": "^1.2.0",
"mocha": "^3.0.0",
"null-loader": "^0.1.1",
"open": "0.0.5",
"phantomjs-prebuilt": "^2.0.0",
"react-addons-test-utils": "^15.0.0",
"react-hot-loader": "^1.2.9",
"rimraf": "^2.4.3",
"style-loader": "^0.13.0",
"url-loader": "^0.5.6",
"webpack": "^1.12.0",
"webpack-dev-server": "^1.12.0"
"dependencies": {
"core-js": "^2.0.0",
"normalize.css": "^4.0.0",
"react": "^15.0.0",
"react-dom": "^15.0.0"

Answer Source

This issue is related to the react-hot-loader package. You are using an old version that relies on the ReactMount.js file being present in the node_modules/react/lib folder.

There is no easy one way fix for that but you have a few options which are:

  1. Try to follow the instructions here: (but I have been unlucky so far)

  2. Remove the hot reloader for react (in your webpack.config remove the 'react-hot' loader)

  3. Update the react-hot-loader package to version 3 (here is how to do so: But note that this package has been in alpha for a while now...

  4. Rollback your react version to one that includes the ReactMount.js in the lib folder (15.0.1 used to have this file not sure when it stopped).