按官方文档创建React Native应用，运行npm start遇spawn cmd ENOENT错误

Hey there, let's get that annoying spawn cmd ENOENT error sorted out for your React Native Expo project.

What's Causing This? #

That error pops up because your Windows system can't find cmd.exe—the command prompt executable. Looking at your error log's PATH entry:

8 verbose lifecycle @~start: PATH: C:\Program Files\nodejs\node_modules\npm\node_modules\npm-lifecycle\node-gyp-bin;C:\xampp\htdocs\native\AwesomeProject\node_modules.bin;C:\Program Files\Git\cmd;C:\xampp\php;C:\Program Files\nodejs;;C:\Users\Administrator\AppData\Roaming\Composer\vendor\bin;C:\xampp\php;C:\Users\Administrator\AppData\Roaming\npm

Notice that C:\Windows\System32 (where cmd.exe lives) is missing from your system's PATH variable. That's the root issue.

Step-by-Step Fix #

• Add System32 to your PATH environment variable

  1. Right-click "This PC" → select "Properties"
  2. Click "Advanced system settings" → go to the "Advanced" tab → hit "Environment Variables"
  3. Under "System variables", find the Path entry and click "Edit"
  4. Add a new line with C:\Windows\System32
  5. Save all changes and close every open command prompt/terminal window

• Verify and Test

  1. Open a brand new terminal window
  2. Run echo %PATH% to confirm C:\Windows\System32 is now in your path
  3. Navigate back to your project folder and run npm start again—this should launch Expo without the error

Bonus Check #

While your Node.js (v10.15.0) and npm (6.4.1) versions are a bit outdated, they should work with Expo 2.6.14. If the PATH fix doesn't resolve things, you could try updating Expo to a more recent version with npm install -g expo-cli, but start with the PATH fix first—it's the most likely culprit here.

内容的提问来源于stack exchange，提问作者roopesh