Understanding the ‘No bundle URL present’ Error in React Native

Understanding the 'No bundle URL present' Error in React Native

18 April 2024 Stephan Petzl Leave a comment Tech-Help

Encountering the ‘No bundle URL present’ error can be a common frustration when working with React Native. This error typically indicates that the application is unable to locate the JavaScript bundle required for the app to run properly.

Common Causes and Solutions

This error can occur due to various reasons, such as the React Native packager not running, issues with the project’s build configuration, or network-related problems. To resolve this error, let’s explore some practical solutions.

Cleaning Build Directories and Restarting the Packager

  1. Start by deleting the iOS build directory to ensure no stale data is causing problems. You can do this by running the following command in your project’s root directory:
    rm -rf ios/build/
  2. Next, make sure no other React Native sessions are running, which might conflict with your current build process. You can terminate any sessions running on the default port (8081) with this command:
    kill $(lsof -t -i:8081)
  3. Now, try rebuilding your iOS application:
    react-native run-ios

To streamline your workflow and avoid encountering this error in the future, consider creating an alias for the above commands. You can add this to your Bash configuration file (.bashrc) with the following command:

echo "alias rni='kill $(lsof -t -i:8081); rm -rf ios/build/; react-native run-ios'" >> ~/.bashrc; source ~/.bashrc

Once set up, you can initiate a React Native iOS build using the ‘rni’ alias.

Adjusting App Transport Security Settings

If the error is related to network security settings on iOS, you might need to modify your info.plist file to allow unsecure connections via localhost. Here’s what you should add:


Ensuring Main.jsbundle is Included

Another potential cause is the absence of the main.jsbundle file in your project. Confirm that this file is included and properly linked to your project. If not, you may need to generate a new bundle and include it in your project’s build directory.

Starting the React Native Packager Manually

Sometimes, you may need to start the React Native packager manually before running your app. Open a new terminal window and execute:

react-native start

Once the packager is running, you can launch your app with:

react-native run-ios

Updating React Native and Dependencies

Ensure your React Native and dependencies are up to date. You can update React Native by running:

react-native upgrade

It’s also a good practice to install your project’s dependencies with:

npm install

or if you prefer using Yarn:

yarn install

Checking Network Configuration

Network issues, such as incorrect DNS settings, can also lead to this error. Make sure your development machine and testing devices are on the same network. Additionally, check your hosts file to ensure ‘localhost’ is properly mapped to


The ‘No bundle URL present’ error in React Native can be resolved by following the steps outlined above. Clearing build directories, adjusting network settings, manually starting the packager, and ensuring up-to-date configurations are all effective strategies. By applying these solutions, developers can minimize disruptions and maintain a smooth development workflow.

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