Я наконец сделал это, используя мою телефонную сеть (должно быть, это был брандмауэр), но потом:
C:\UserXXXX\Desktop\js REACT>create-react-app react-app
Creating a new React app in C:\UserXXXX\\Desktop\js REACT\react-app.
Installing packages. This might take a couple of minutes.
Installing react, react-dom, and react-scripts...
npm ERR! code ENOTFOUND
npm ERR! errno ENOTFOUND
npm ERR! network request to http://registry.npmjs.org/posix-character-
classes/-/posix-character-classes-0.1.1.tgz failed, reason: getaddrinfo ENOTFOUND
registry.npmjs.org registry.npmjs.org:80
npm ERR! network This is a problem related to network connectivity.
npm ERR! network In most cases you are behind a proxy or have bad network settings.
npm ERR! network
npm ERR! network If you are behind a proxy, please make sure that the
npm ERR! network 'proxy' config is set properly. See: 'npm help config'
npm ERR! A complete log of this run can be found in:
npm ERR! C:\UserXXXX\AppData\Roaming\npm-cache\_logs\2018-12-
11T10_28_30_314Z-debug.log
Aborting installation.
npm install --save --save-exact --loglevel error react react-dom react-scripts has failed.
Deleting generated file... node_modules
Deleting generated file... package.json
Deleting react-app / from C:\UserXXXX\Desktop\js REACT
Done.