How to solve access blocked error in n8n?

Questions
1

I’ve set up a project on the google console, but whenever I try to log in to n8n, it says it’s blocked. ( Google sheets )
I’d tried setting it up last week and it worked fine, but now I get this error:

Describe the problem/error/question

What is the error message (if any)?

Please share your workflow

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Share the output returned by the last node

Information on your n8n setup

  • n8n version:
  • Database (default: SQLite):
  • n8n EXECUTIONS_PROCESS setting (default: own, main):
  • Running n8n via (Docker, npm, n8n cloud, desktop app):
  • Operating system:
3

@jordahn check ur OAuth client redirect URI in Google Cloud. n8n’s callback URL changes if your instance URL changed or creds were regenerated. Copy the exact OAuth Redirect URL from the n8n credential modal into Authorized redirect URIs on Google’s side—mismatch throws “access blocked” instantly.

Reconnect the Sheets cred after fixing the URI.

4

hey @jordahn checking back in — did fixing the redirect URI sort it out? if u’re still stuck, the OTHER common cause for that exact “access blocked” error on Sheets is the OAuth consent screen sitting in Testing mode with empty (or wrong) Test Users list. u’d see the same error even with the URI matching perfectly. quick fix: Google Cloud Console → APIs & Services → OAuth consent screen → scroll to Test users → add the google account u’re authenticating with. happy to dig deeper if its still acting up.