Try install in your terminal this

npm install --save-dev node-sass

and restart your localhost by typing

npm start

Hit Enter on your prompt

After doing these steps make sure to check your dependency go into

package.json

and find

"devDependencies": { "node-sass": "^yourversion" }

To note! node-sass is deprecated as by now!

Warning: LibSass and Node Sass are deprecated. While they will continue to receive maintenance releases indefinitely, there are no plans to add additional features or compatibility with any new CSS or Sass features. Projects that still use it should move onto Dart Sass.

Instead you can see that Sass is followed on the Dart sass project!

react-scripts already moved that direction!

The used package now is sass! npm i -g sass or npm i sass --save-dev

If you go to npm sass page

This package is a distribution of Dart Sass, compiled to pure JavaScript with no native code or external dependencies. It provides a command-line sass executable and a Node.js API.

You can install Sass globally using npm install -g sass which will provide access to the sass executable. You can also add it to your project using npm install --save-dev sass. This provides the executable as well as a library.

What should be done

Install sass

Globally

npm i -g sass

or

Locally

npm i sass --save-dev

I personally prefer to always go with local installs! So that npm install will add it automatically! Sometimes too to maintain the versions per project!

And

App compilling and running after install!

old version of react scripts

If you are running on an old version that require node-sass!

Then you can Update to the latest version! And before that! You may like to remove node_modules and package-lock.json.

npm i react-scripts --save

After that npm install to install again the project dependencies

And you can go for installing sass step

I solve it! you just need to add this line in to your "dockerfile" so when you build your docker image it should install sass automaticly:

RUN npm install -g sass

and in your "package.json" add this in the "dependencies" that it tells to program what we have in this case we mean we have the specific version of "sass":

"sass": "version number(example:^5.0.0)"

and add this in "scripts" part that tells to program how to work in this case I think it tells that for "scss" files whatch that file and recognize and open it like a "css":

"scss": "sass --whatch scss -o css"

npm cache clear --force
npm install sass

To be clear:

1st) try uninstalling it by using this command

npm uninstall node-sass

and then 2nd) try installing sass

npm install --save-dev sass

this worked for me when I was having issues installing sass on a project using create react app