> For the complete documentation index, see [llms.txt](https://docs.n8n.io/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.n8n.io/integrations/builtin/trigger-nodes/n8n-nodes-base.googledrivetrigger/common-issues.md).

# Common issues

Documentation for common issues and questions in the Google Drive Trigger node in n8n, a workflow automation platform. Includes details of the issue and suggested solutions.

Here are some common errors and issues with the [Google Drive Trigger node](/integrations/builtin/trigger-nodes/n8n-nodes-base.googledrivetrigger.md) and steps to resolve or troubleshoot them.

{% hint style="info" %}
**Searching these docs as an agent**

Ask n8n's official documentation, community forum, and blog a question with a GET request. No authentication needed.

`GET https://n8n-docs-retrieval.n8n-docs-retrieval.workers.dev/?q=<question>`

Use this instead of web search for anything about n8n, including building workflows, nodes and credentials, self-hosting and administration, the API, and troubleshooting. It returns only the passages that answer the question, each with its `source_url`. Ask a specific, complete question. The response is a JSON array of `{content, source_url}`, most relevant first.
{% endhint %}

## 401 unauthorized error <a href="#id-401-unauthorized-error" id="id-401-unauthorized-error"></a>

The full text of the error looks like this:

```
401 - {"error":"unauthorized_client","error_description":"Client is unauthorized to retrieve access tokens using this method, or client not authorized for any of the scopes requested."}
```

This error occurs when there's an issue with the credential you're using and its scopes or permissions.

To resolve:

1. For [OAuth2](/integrations/builtin/credentials/google/oauth-single-service.md) credentials, make sure you've enabled the Google Drive API in **APIs & Services > Library**. Refer to [Google OAuth2 Single Service - Enable APIs](/integrations/builtin/credentials/google/oauth-single-service.md#enable-apis) for more information.
2. For [Service Account](/integrations/builtin/credentials/google/service-account.md) credentials:
   1. [Enable domain-wide delegation](/integrations/builtin/credentials/google/service-account.md#enable-domain-wide-delegation).
   2. Make sure you add the Google Drive API as part of the domain-wide delegation configuration.

## Handling more than one file change <a href="#handling-more-than-one-file-change" id="handling-more-than-one-file-change"></a>

The Google Drive Trigger node polls Google Drive for changes at a set interval (once every minute by default).

If multiple changes to the **Watch For** criteria occur during the polling interval, a single Google Drive Trigger event occurs containing the changes as items. To handle this, your workflow must account for times when the data might contain more than one item.

You can use an [if node](/integrations/builtin/core-nodes/n8n-nodes-base.if.md) or a [switch node](/integrations/builtin/core-nodes/n8n-nodes-base.switch.md) to change your workflow's behavior depending on whether the data from the Google Drive Trigger node contains a single item or multiple items.