Module not found: Error: Can't resolve 'module-name'

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Root Cause

This error indicates that Node.js or your module bundler (Webpack, Rollup, etc.) cannot locate the package or file you are trying to import. The most common causes are a simple typo in the package name or file path, forgetting to run `npm install` after pulling new code, or a missing file extension in your import statement. It can also occur if you are importing a local file using a relative path, but the path is incorrect relative to the current file's location.

Fix / Solution

First, verify that the module is listed in your `package.json` and that you have run `npm install`. Double-check the spelling of the import statement. For local files, ensure the relative path is correct (e.g., `../components/Button` instead of `./components/Button`). If using TypeScript or specific bundlers, check if your configuration requires explicit file extensions for certain file types.

Code Snippet

// ❌ Typo or missing dependency
import { SomeComponent } from 'react-domm';

// ❌ Incorrect relative path
import utils from './utils'; // When utils is in parent directory

// ✅ Correct path and dependency
import { SomeComponent } from 'react-dom';
import utils from '../utils';