Fix GitHub Copilot Chat 'Could not parse ov' Error in Visual Studio 2022

How to Fix It

Solution 1: Update Visual Studio to Version 17.14.7 or Later (Official Fix)

This is the most reliable fix, as confirmed by the Microsoft Developer Community thread. The fix was released in Visual Studio 2022 version 17.14.7.

1. Open Visual Studio 2022.
2. Go to Help > Check for Updates.
3. If an update to version 17.14.7 or later is available, click Download and then Update.
4. After the update completes, restart Visual Studio.
5. Open a project and test Copilot Chat by asking a simple question like "hi" or "what does this file do?"
6. If the error no longer appears, the fix is successful.

If you are on Visual Studio 2022 version 17.14.6, the update should resolve the issue. The official documentation does not provide a manual patch; the only official solution is to update to the fixed version.

Solution 2: Remove and Re-add Your GitHub Account (For Token Corruption)

If updating does not fix the error, or if you see the "token is empty" error in the logs, follow these steps to refresh your authentication token.

1. In Visual Studio, go to File > Account Settings (or Environment > Accounts in some versions).
2. Find your GitHub account in the list of connected accounts.
3. Click Remove to sign out.
4. Close Visual Studio completely.
5. Reopen Visual Studio and go back to File > Account Settings.
6. Click Add an account and select GitHub.
7. Sign in with your GitHub credentials. Ensure you authorize the Visual Studio application if prompted.
8. After signing in, open a project and test Copilot Chat.

Note: Source 3 reports that "Removing and adding account doesn't help" for some users. This indicates that while token corruption can cause the error, it is not the root cause for everyone. If this does not work, proceed to Solution 3.

Solution 3: Clear Visual Studio Cache and Session Data

Corrupted session data can cause parsing errors. Clearing the cache forces Copilot to start fresh.

1. Close all instances of Visual Studio.
2. Navigate to the .vs folder in your solution directory. This folder is hidden by default. To find it:
   • Open your project folder in File Explorer.
   • Click View > Show > Hidden items.
   • Look for a folder named .vs.
3. Inside .vs, navigate to the subfolder that contains copilot-chat. The path typically looks like: .vs\YourSolutionName\copilot-chat\. There may be multiple subdirectories with hexadecimal names (e.g., 04739bed).
4. Delete the entire copilot-chat folder. This removes all persisted session data.
5. Also delete the CopilotIndices folder if it exists (e.g., .vs\YourSolutionName\CopilotIndices). This removes cached code context data.
6. Reopen Visual Studio and reload your solution.
7. Test Copilot Chat.

If you do not want to delete the entire folder, you can also try clearing the Visual Studio cache via Tools > Options > Environment > Import and Export Settings > Reset all settings, but this is more aggressive and may reset other preferences. The folder deletion method is more targeted.

Solution 4: Check Proxy Configuration

If your network uses a proxy, ensure the COPILOT_USE_DEFAULTPROXY environment variable is set correctly.

1. Close Visual Studio.
2. Open a command prompt as Administrator.
3. To check the current value, run:

   echo %COPILOT_USE_DEFAULTPROXY%
   

   If it returns False or is empty, you may need to set it to True.
4. To set the variable, run:

   setx COPILOT_USE_DEFAULTPROXY True
   

5. Restart Visual Studio.
6. Test Copilot Chat.

If you do not use a proxy, this is unlikely to help. The official documentation does not provide guidance on this variable, so this is a community-suggested workaround. If the error persists, revert the variable by setting it to False or deleting it.

Solution 5: Reinstall the GitHub Copilot Extension

If none of the above work, a fresh installation of the extension may resolve underlying corruption.

1. In Visual Studio, go to Extensions > Manage Extensions.
2. Find GitHub Copilot in the list.
3. Click Uninstall.
4. Close Visual Studio and follow any prompts to complete the uninstallation.
5. Reopen Visual Studio.
6. Go to Extensions > Manage Extensions > Online.
7. Search for "GitHub Copilot" and click Download.
8. After installation, restart Visual Studio.
9. Sign in to GitHub again when prompted.
10. Test Copilot Chat.

This ensures you have the latest version of the extension, which may include fixes beyond the Visual Studio update.

If Nothing Works

Escalate to Microsoft Developer Community

The original issue reporter created a thread on the Microsoft Developer Community, which led to the fix. If you have tried all solutions above and the error persists, create your own thread at: https://developercommunity.visualstudio.com/

Include the following information in your report:

• Visual Studio version (e.g., 17.14.6)
• Copilot Chat extension version
• OS version (e.g., Windows 10)
• The exact error message: "Could not parse ov"
• The full log output from the Copilot Chat output window. To capture logs:
  1. In Visual Studio, go to View > Output.
  2. In the "Show output from" dropdown, select GitHub Copilot.
  3. Reproduce the error by asking a question in Copilot Chat.
  4. Copy the entire log content and paste it into your report.
• Steps you have already taken to troubleshoot.

Check GitHub Copilot Status

Verify that the GitHub Copilot service itself is not experiencing an outage. Visit: https://www.githubstatus.com/

If there is a reported incident, wait for it to be resolved before continuing troubleshooting.

Use a Workaround: Disable and Re-enable Copilot

As a temporary workaround, you can disable and re-enable Copilot to reset its state.

1. In Visual Studio, go to Tools > Options > GitHub Copilot.
2. Uncheck Enable GitHub Copilot.
3. Click OK.
4. Restart Visual Studio.
5. Go back to Tools > Options > GitHub Copilot and re-check Enable GitHub Copilot.
6. Click OK and restart Visual Studio again.
7. Test Copilot Chat.

This may not fix the underlying parsing bug, but it can sometimes clear transient state issues.

Use Copilot in a Different Environment

If you need Copilot immediately, consider using it in a different IDE while waiting for a fix. The official documentation supports Copilot in:

• Visual Studio Code (with the GitHub Copilot Chat extension)
• JetBrains IDEs (with the GitHub Copilot plugin)
• Xcode (with the GitHub Copilot extension)
• Windows Terminal (with Terminal Chat)
• GitHub.com (via the web interface)

Each of these environments has its own setup instructions, but they are less likely to have the same parsing bug.

How to Prevent It

Keep Visual Studio Updated

The most effective prevention is to always run the latest version of Visual Studio. Enable automatic updates:

1. Go to Tools > Options > Environment > Updates.
2. Select Automatically download updates.
3. Click OK.

This ensures you receive bug fixes like the one in 17.14.7 as soon as they are released.

Maintain a Stable GitHub Authentication

Avoid frequently signing in and out of GitHub accounts in Visual Studio, as this can lead to token corruption. If you must switch accounts, always use the Account Settings dialog to sign out properly rather than just closing the IDE.

Avoid Corrupting Session Data

Do not manually edit or delete files inside the .vs folder while Visual Studio is running. Always close Visual Studio before modifying any files in that directory. If you use source control, consider adding the .vs folder to your .gitignore file to prevent accidental commits of session data.

Monitor Proxy Settings

If your network configuration changes (e.g., you switch from a corporate network to a home network), verify that the COPILOT_USE_DEFAULTPROXY environment variable is set appropriately. You can check this by running echo %COPILOT_USE_DEFAULTPROXY% in a command prompt. If you encounter errors after a network change, resetting this variable may help.

Use the Official Documentation for Setup

Follow the official GitHub Copilot setup instructions for Visual Studio 2022 to ensure a correct initial configuration:

• Install Visual Studio 2022 version 17.8 or later.
• Install the GitHub Copilot extension from the Visual Studio Marketplace.
• Add your GitHub account to Visual Studio via File > Account Settings.
• Verify your subscription is active on GitHub.com.

These steps are documented in the official quickstart guide and reduce the likelihood of configuration-related errors.