Visual Studio Code "Error while fetching extensions. XHR failed"

Troubleshooting 'Error while fetching extensions. XHR failed' in VS Code

Learn to diagnose and resolve the common 'XHR failed' error when Visual Studio Code struggles to fetch extensions, ensuring uninterrupted development.

Visual Studio Code (VS Code) is a powerful and popular editor, largely due to its rich ecosystem of extensions. However, encountering the error message "Error while fetching extensions. XHR failed" can be a frustrating roadblock. This error typically indicates a problem with VS Code's ability to communicate with the extension marketplace, often stemming from network issues, proxy configurations, or security software. This article will guide you through common causes and effective solutions to get your extension marketplace working again.

Understanding the 'XHR failed' Error

XHR stands for XMLHttpRequest, which is an API used by web browsers and applications (like VS Code, which is built on Electron, essentially a web browser) to send HTTP or HTTPS requests to a web server and load the server's response back into the application. When VS Code tries to fetch extensions from the marketplace, it uses XHR requests. An 'XHR failed' error means that this request could not be completed successfully. This failure can be due to various reasons, including network connectivity problems, firewall blocks, proxy server misconfigurations, or even issues with the marketplace server itself.

Flowchart of VS Code Extension Fetching Process

Common Causes and Solutions

The 'XHR failed' error is usually a symptom of an underlying network or configuration problem. Addressing these issues systematically will help you pinpoint and resolve the root cause.

1. Check Network Connectivity

Ensure your internet connection is stable and working. Try accessing other websites or services to confirm general connectivity. Sometimes, a temporary network outage or a weak Wi-Fi signal can cause this error.

2. Disable VPN/Proxy (Temporarily)

If you are using a VPN or a proxy server, try temporarily disabling it. These services can sometimes interfere with VS Code's ability to connect to the extension marketplace. If disabling it resolves the issue, you may need to configure your proxy settings within VS Code or your system.

3. Configure Proxy Settings in VS Code

If you are behind a corporate proxy, VS Code needs to be explicitly configured to use it. You can set proxy settings in VS Code's settings.json file. Open the Command Palette (Ctrl+Shift+P or Cmd+Shift+P), type Preferences: Open Settings (JSON), and add or modify the following settings:

{
    "http.proxy": "http://your.proxy.server:port",
    "http.proxyStrictSSL": false,
    "http.proxyAuthorization": "Basic YOUR_BASE64_ENCODED_CREDENTIALS"
}

Example VS Code proxy configuration in settings.json

1. Check Firewall and Antivirus Software

Your firewall or antivirus software might be blocking VS Code's outgoing connections to the marketplace. Temporarily disable them to see if the error resolves. If it does, you'll need to add an exception for VS Code in your security software.

2. Clear VS Code Cache

Corrupted cache files can sometimes lead to unexpected behavior. You can try clearing VS Code's cache. The cache location varies by operating system:

Windows

Delete the contents of %APPDATA%\Code\Cache and %APPDATA%\Code\CachedData.

macOS

Delete the contents of ~/Library/Application Support/Code/Cache and ~/Library/Application Support/Code/CachedData.

Linux

Delete the contents of ~/.config/Code/Cache and ~/.config/Code/CachedData.

1. Update VS Code

Ensure your VS Code installation is up to date. Bugs related to network communication are often patched in newer versions. Go to Help > Check for Updates or download the latest version from the official website.

2. Check Marketplace Status

Occasionally, the VS Code extension marketplace itself might be experiencing downtime or issues. Check the official VS Code status page or relevant community forums to see if there are any reported outages.

Advanced Troubleshooting

If the above steps don't resolve the issue, you might need to delve deeper into network diagnostics or consider a fresh installation.

1. Run VS Code with --ignore-gpu-blacklist

In rare cases, GPU rendering issues can affect Electron apps. Try launching VS Code from your terminal with the --ignore-gpu-blacklist flag. This is a long shot but has helped some users with obscure rendering-related network issues.

2. Reinstall VS Code

As a last resort, a clean reinstallation of VS Code can resolve persistent issues. Make sure to back up your settings and extensions list before proceeding. Uninstall VS Code, delete any remaining configuration folders (as mentioned in the cache clearing step), and then perform a fresh installation.