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

# Common issues with Google Drive Trigger in Duaer

Common Google Drive Trigger issues in Duaer: 401 and several file changes at once.
## 401 unauthorized_client <a href="#id-401-unauthorized-error" id="id-401-unauthorized-error"></a>

The full error looks like 401 - {"error":"unauthorized_client", ...}. The credential has the wrong permissions or scopes:

- [OAuth2 credential](/integrations/builtin/credentials/google/oauth-generic.md#scopes): enable Google Drive API under APIs & Services > Library in the Google Cloud console.
- [Service account credential](/integrations/builtin/credentials/google/service-account.md): turn on domain-wide delegation for the service account in the Google Workspace admin console and add the scopes Google Drive API needs.

## Several file changes at once <a href="#handling-more-than-one-file-change" id="handling-more-than-one-file-change"></a>

Google Drive Trigger polls on Poll Times, every minute by default. Changes matching Watch For between polls come out as several items in one run. Make later nodes handle several items, and split them with [If](/integrations/builtin/core-nodes/duaer-nodes-base.if.md) if needed.
## Questions

### Why does the Duaer Google Drive Trigger output several items?

The Duaer Google Drive Trigger polls, so every change between two polls comes out in the same run.