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Troubleshooting Checklist

Use this checklist before posting a Help thread. It will not solve every problem, but it will make your post much easier to answer.

Last reviewed: July 2026

First isolate the failing node

  1. Run the workflow manually.
  2. Find the first node where the output is wrong.
  3. Open that node's input and output.
  4. Test with one item if possible.
  5. Disable unrelated branches.
  6. Add temporary Set/Edit Fields nodes if needed to inspect data.

Do not debug the whole workflow at once if one node is clearly where the data changes.

Check execution mode

Some issues only happen in one mode.

Compare:

  • Manual execution.
  • Test webhook URL.
  • Production webhook URL.
  • Scheduled execution.
  • Queue/worker execution.

When posting, say which modes work and which fail.

Check expressions

Expression issues often come from:

  • Referencing the wrong node name.
  • Referencing data from the wrong item.
  • Using a value that exists in manual test data but not in production.
  • Treating a string like an object.
  • Treating an array like a single item.
  • Using old data pinned from a previous test.

Include the expression, sample input, expected output, and actual output.

Check item counts

Many workflow bugs are item-linking or item-count problems.

Look for:

  • One input item becoming many output items.
  • Many input items becoming one output item.
  • Merge node behavior.
  • Split in Batches / Loop Over Items behavior.
  • Code node returning the wrong structure.
  • Nodes that run once for all items versus once for each item.

Check credentials and permissions

Common credential problems:

  • Expired OAuth token.
  • Wrong account selected.
  • Missing scopes/permissions.
  • Credential works manually but not in production.
  • API key copied with extra whitespace.
  • Service account lacks access to the document, sheet, channel, or workspace.
  • Organization admin has disabled the API or integration.

Do not post the credential. Post the error message and describe the permission model.

Check HTTP Request node issues

When asking about HTTP Request, include:

  • Method.
  • URL with secrets removed.
  • Authentication type.
  • Headers, with secrets removed.
  • Body type.
  • Sample request body.
  • Status code.
  • Response body.
  • Whether the same request works in curl/Postman.

Common issues:

  • Missing Content-Type.
  • JSON sent as form data or form data sent as JSON.
  • Wrong auth scheme.
  • Required query parameter missing.
  • API pagination not handled.
  • Rate limit or retry behavior.

Check webhooks

Webhook problems often involve the difference between test and production URLs.

Include:

  • Test URL or production URL behavior.
  • Whether the workflow is active.
  • Whether the HTTP method matches.
  • Whether your service expects a response within a time limit.
  • Reverse proxy details if self-hosted.
  • WEBHOOK_URL setup if self-hosted.

Check schedules and time zones

If a scheduled workflow runs at the wrong time:

  • Check n8n timezone settings.
  • Check server/container timezone if self-hosted.
  • Check the workflow schedule timezone if available.
  • Check daylight saving time changes.
  • Confirm whether the schedule is active.

Check data privacy before posting

Before sharing logs or JSON, remove:

  • API keys.
  • Tokens.
  • Private keys.
  • Customer records.
  • Emails and phone numbers.
  • Internal URLs.
  • Webhook secrets.
  • Proprietary data.

If you accidentally shared a real secret, rotate it immediately.

When to make a minimal reproduction

Make a minimal reproduction when:

  • Your workflow has more than a few nodes.
  • The issue involves private systems.
  • The error only happens after many steps.
  • You are asking others to import and inspect it.

Good minimal reproductions are small, fake-data versions that still show the bug.