> 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.gmailtrigger/common-issues.md).

# Common issues with Gmail Trigger in Duaer

Common Gmail Trigger issues in Duaer: 401 and several emails 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 Gmail 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 Gmail API needs.

## Several emails at once <a href="#handling-more-than-one-email" id="handling-more-than-one-email"></a>

Gmail Trigger polls on Poll Times, every minute by default. Emails that arrive 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

### How often does the Duaer Gmail Trigger check for mail?

The Duaer Gmail Trigger polls on Poll Times, every minute by default.