React npm start con't run and open the localhost:3000

[mohammad-qb]

app@0.1.0 start C:\Users\mohammad ahmad\Desktop\React Projects\app
react-scripts start

Starting the development server...

events.js:174
throw er; // Unhandled 'error' event
^

Error: spawn cmd ENOENT
at Process.ChildProcess._handle.onexit (internal/child_process.js:240:19)
at onErrorNT (internal/child_process.js:415:16)
at process._tickCallback (internal/process/next_tick.js:63:19)
Emitted 'error' event at:
at Process.ChildProcess._handle.onexit (internal/child_process.js:246:12)
at onErrorNT (internal/child_process.js:415:16)
at process._tickCallback (internal/process/next_tick.js:63:19)
npm ERR! code ELIFECYCLE
npm ERR! errno 1
npm ERR! app@0.1.0 start: react-scripts start
npm ERR! Exit status 1
npm ERR!
npm ERR! Failed at the app@0.1.0 start script.
npm ERR! This is probably not a problem with npm. There is likely additional logging output above.

npm ERR! A complete log of this run can be found in:
npm ERR! C:\Users\mohammad ahmad\AppData\Roaming\npm-cache_logs\2019-05-15T20_48_25_193Z-debug.log

[alexreu]

Hi, i confirm that i have the same problem , since yesterday

[alexreu]

Finally i downgrade my react-scripts in package.json to this version : "react-scripts": "^2.1.8" and it works for me

[SId02]

Hi, I have the same problem , since morning

When I am trying to create new app using create-react-app and trying to start it thorwing below error. Though old apps are still running. Please help me in this as I have already tried all solutions available on stackoverflow and issue list.

OS: WIN 8,
NODE : v10.15.3
NPM: 6.4.1

create-react-app

react@16.8.6
react-scripts@3.0.1
react-dom@16.8.6

React npm start throwing the error and not opening the localhost:3000

Error On Cmd:

my-app@0.1.0 start C:\UI Dev\React-Demo\my-app
react-scripts start

Starting the development server...

events.js:174
throw er; // Unhandled 'error' event
^

Error: spawn cmd ENOENT
at Process.ChildProcess._handle.onexit (internal/child_process.js:240:19)
at onErrorNT (internal/child_process.js:415:16)
at process._tickCallback (internal/process/next_tick.js:63:19)
Emitted 'error' event at:
at Process.ChildProcess._handle.onexit (internal/child_process.js:246:12)
at onErrorNT (internal/child_process.js:415:16)
at process._tickCallback (internal/process/next_tick.js:63:19)
npm ERR! code ELIFECYCLE
npm ERR! errno 1
npm ERR! my-app@0.1.0 start: react-scripts start
npm ERR! Exit status 1
npm ERR!
npm ERR! Failed at the my-app@0.1.0 start script.
npm ERR! This is probably not a problem with npm. There is likely additional log
ging output above.

npm ERR! A complete log of this run can be found in:
npm ERR! C:\Users\MyPC\AppData\Roaming\npm-cache_logs\2019-05-16T08_07_
48_884Z-debug.log

[alexreu]

to work around the problem i use this old version of react-scripts :
react-scripts@2.1.8

[alteredco]

Here is the message I get in my terminal, it seems to be something to do with the version of babel-jest in the react-scripts 3.0.1 package:
The react-scripts package provided by Create React App requires a dependency: "babel-jest": "^24.8.0" However, a different version of babel-jest was detected higher up in the tree: npm ls babel-jest state-app@0.1.0 └─┬ react-scripts@3.0.1 ├── babel-jest@24.8.0 └─┬ jest@24.7.1 └─┬ jest-cli@24.8.0 └─┬ jest-config@24.8.0 └── babel-jest@24.8.0 deduped

Once I rolled back to react-scripts 3.0.0 npm start works fine.

[creativetim]

Was helping someone with this problem on their Windows box and came across the following SO article and it did the trick.

I checked system variables one more time and found the cause of the problem: missing C:\Windows\System32\ variable. I added it and that solved my problem

More detailed instructions that didn't get labeled as the answer:

Goto > Control Panel\System and Security\System\Advance system setting\Enviroment variable and set system variables path C:\Windows\System32\ variable and restart your System.

Took a fair amount of Googling to arrive there. Hopefully this helps people out so they aren't forced to try a particular, now outdated, version of react-scripts just to get their React app running.

[rafafauzi]

i have some problem too, check yours environtment variable first, this is mine and its work

[Smytt]

Finally i downgrade my react-scripts in package.json to this version : "react-scripts": "^2.1.8" and it works for me

This worked for me also. Pretty weird, though.

[m-vignesh]

Finally i downgrade my react-scripts in package.json to this version : "react-scripts": "^2.1.8" and it works for me

This worked for me also. Pretty weird, though.

So, does that mean the latest version of React (v3.2) is not usable ??

[waqaryounis7564]

Finally i downgrade my react-scripts in package.json to this version : "react-scripts": "^2.1.8" and it works for me

This worked for me also. Pretty weird, though.

works for me thanks

[CanaanGM]

Yup, downgrading works~!

[waqaryounis7564]

instead of npx, use npm i create-react-app.

[prathapgunasekara]

Downgrading works (y)

[chamath-naveen]

Yep!! Downgrading works for me