Fix Vega Studio Build Issues
This page helps you resolve common issues when building and running apps with Vega Studio in VS Code.If you don't find a solution to your specific problem here, post an issue in Developer Forum for additional support.
Port forwarding fails with "operation unsuccessful" error
Cause: This error occurs when the simulator isn't running.
Solution:
- Go to Kepler Studio panel > Devices.
- If it shows VirtualDevice:Tv (Not running), go to Projects section and click the "play" button next to your project name.
Error loading webview in VS Code
While using VS Code, your screen might display the following message:
Error loading webview
Cause: This error happens when multiple instances of VS Code are open.
Solution: At the command prompt, run force quit all
to quit all instances and restart VS Code.
React Native Tools extension fails to activate when creating new project
When creating a new project, you might receive this error message:
[Error] Failed to activate the React Native Tools extension (error code 702)
Cause: VS Code workspace configuration issues prevent the React Native Tools extension from loading properly.
Solution: Open your project as a workspace in the VS Code toolbar (File > Open Workspace from File) and save it as a new workspace.
React Native Packager is already running when trying to launch app
When trying to launch your app, you might see this error message:
Failed to execute command. React Native Packager is already running
Cause: This issue happens when you have a multi-project workspace and an app is currently running.
Solution: Stop the packager before launching another app. In the VS Code command palette, enter React Native: Stop Packager.
No project templates appear when selecting a template
Cause: Environment variables from the Vega SDK aren't properly loaded in the current VS Code session.
Solution: Source the environment file from the Vega SDK installed directory. At the command prompt, open VS Code using code
.
Build or launch fails due to port conflicts
Cause: Another process is using the required port.
Solution: Choose a different port to resolve the port conflict.
Fast Refresh feature doesn't update app when making code changes
Cause: Port forwarding connection issues prevent Fast Refresh from communicating with the device.
Solution: Reset your reverse port forwarding connection and relaunch your app:
- Check the current list:
kepler exec vda reverse —list
- Remove all list:
kepler exec vda reverse —remove-all
- Relaunch your app.
Line-by-line-debugging isn’t working
Cause: Developer mode may not be properly configured or the debug host configuration is missing.
Solution: Verify developer mode and check shared_preferences.json
to resolve the issue. See Configure Developer Mode on Fire TV Stick
To enable line-by-line debugging on the custom port, add the following configuration in shared_preferences.json
file:
{
"debug_http_host": "localhost:<PORT>"
}
Make sure to replace <PORT>
with the actual port number you’re using.
Related topics
Last updated: Sep 30, 2025