How to handle “401 unauthorized” from OpenAI after rotating keys in n8n?

If you're encountering a "401 Unauthorized" error in n8n after rotating your OpenAI API keys, you need to update your credentials in n8n. This happens because your old API key has been invalidated, and n8n is still trying to use it for authentication with OpenAI's services.

 

Understanding the 401 Unauthorized Error in n8n

 

A 401 Unauthorized error occurs when the authentication credentials (in this case, your API key) provided to a service are invalid or expired. When you rotate OpenAI API keys for security purposes, the old key becomes invalid, and any service using that key, including n8n workflows, will fail with this error.

 

Step 1: Confirm the Issue

 

First, verify that the 401 error is indeed due to an invalid API key:

// Example of error message you might see in n8n
{
  "error": {
    "message": "Incorrect API key provided: sk-.....",
    "type": "invalid_request_error",
    "param": null,
    "code": "invalid_api_key"
  }
}

 

Step 2: Access n8n Credentials

 

1. Log in to your n8n instance.
2. Click on the Settings icon in the left sidebar (gear icon).
3. Select Credentials from the menu.

 

Step 3: Find Your OpenAI Credentials

 

1. In the Credentials section, look for your OpenAI credentials.
2. You can use the search bar to find them by typing "OpenAI".
3. Click on the credential entry you need to update.

 

Step 4: Update the API Key

 

1. Once you've opened the credential configuration, you'll see the API Key field.
2. Replace the old API key with your new OpenAI API key.
3. The API key format should look like: sk-...
4. Ensure there are no extra spaces before or after the key.

// Example of updating the API key field
// Old (invalid) key: sk-oldKeyThatNoLongerWorks123456789
// New key: sk-newValidKeyFromOpenAI987654321

 

Step 5: Save Your Updated Credentials

 

1. After entering the new API key, click the Save button.
2. n8n will confirm that the credentials have been updated.

 

Step 6: Test Your Workflow

 

1. Navigate back to your workflow that was experiencing the 401 error.
2. Click on the OpenAI node in your workflow.
3. Click on the Execute Node button to test if the connection works now.
4. You should no longer see the 401 Unauthorized error if the key was updated correctly.

 

Step 7: Debugging Persistent Issues

 

If you're still encountering 401 errors after updating your credentials, try these troubleshooting steps:

 

Check for Multiple Credential Instances

 

1. Return to the Credentials section.
2. Search for "OpenAI" again to ensure you haven't missed any credential entries.
3. Update all OpenAI credential instances with your new API key.

 

Verify API Key Permissions

 

1. Go to the OpenAI dashboard at https://platform.openai.com/account/api-keys.
2. Verify that your new API key has the necessary permissions for the operations you're performing.
3. Check if there are any usage limits or restrictions on the new key.

// Example of checking API key in the OpenAI dashboard
// Navigate to: https://platform.openai.com/account/api-keys
// Look for your key and check its status and permissions

 

Check for Workspace Issues

 

If you're using n8n in a multi-user environment:

1. Ensure you have the necessary permissions to update credentials.
2. Check if the workflow is using shared credentials or personal credentials.
3. Update the appropriate credential set.

 

Step 8: Implement Key Rotation Best Practices

 

To avoid disruptions during future key rotations:

 

Create a New Credential Before Invalidating the Old One

 

1. Create a new API key in OpenAI.
2. Create a new credential in n8n with the new key.
3. Update your workflows to use the new credential.
4. Only after confirming everything works, delete the old API key from OpenAI.

 

Use Environment Variables (Advanced)

 

For more advanced setups, consider using environment variables:

// In your n8n environment configuration (e.g., .env file)
OPENAI_API_KEY=sk-yourNewApiKey

// In n8n, use the expression syntax to reference the environment variable
{{$env.OPENAI_API_KEY}}

This approach allows you to update the key in one place without editing multiple credential entries.

 

Step 9: Monitor and Test

 

After updating your credentials:

1. Monitor your workflows for the next 24 hours.
2. Set up error notifications if you haven't already:

• Go to Settings > Workflow Settings.
• Configure Error Workflow to notify you of any authentication failures.

 

Conclusion

 

Handling a 401 Unauthorized error after rotating OpenAI API keys in n8n is straightforward once you know where to update your credentials. By following this guide, you should be able to quickly resolve authentication issues and implement best practices for future API key rotations to minimize disruption to your workflows.

Remember that API keys are sensitive information, so always handle them securely and follow your organization's security policies regarding credential management and rotation schedules.