a year ago
I need help with this error. ERROR REPORTED BY - OAuth 2.0 Playground Error: Insufficient parameters for OAuth2 callback. More details: Received following query parameters: {} Failed to connect. The window can be closed now.
I'm using the n8n opensource, a repository on GitHub and hosted on the Railway server. In the Workflow dashboard, when I try to connect the credential to the Google Contacts - Get All node, it returns the error below.
ERROR REPORTED BY - n8n Error: Client authentication failed (e.g., unknown client, no client authentication included, or unsupported authentication method). More details: Failed to connect. The window can be closed now.
Why does this happen? Could you please help me with this error?
2 Replies
a year ago
Hey there! We've found the following might help you get unblocked faster:
- 🧵 Google Drive API OAuth Redirect Issue on n8n
- 🧵 N8n (w/ Webhook Processes) Does not connect with Google Sheets OAuth2 API
- 🧵 n8n Google OAuth 404 Not found
If you find the answer from one of these, please let us know by solving the thread!
9 days ago
This looks like an OAuth configuration problem rather than a Google Contacts or Railway networking problem. The two errors point to the OAuth callback/client configuration: Google is returning to n8n without the authorization parameters n8n expects, and n8n then cannot authenticate the OAuth client. First make sure the n8n service has a public Railway HTTPS domain and that n8n knows that public URL. In Railway, set N8N_PROTOCOL=https and WEBHOOK_URL=https://YOUR-N8N-DOMAIN and redeploy the service. Railway’s current n8n deployment guide specifically requires WEBHOOK_URL to be the full public HTTPS URL so n8n generates externally reachable URLs correctly. Then open the Google credential inside n8n and copy the OAuth Redirect URL shown by n8n itself. In Google Cloud Console, open the OAuth 2.0 Client ID used by this credential and add that exact URL under Authorized redirect URIs. Do not substitute localhost, the Railway internal hostname, an old Railway domain, or a URL with a different path/trailing slash: OAuth callback URLs are exact-match values. Also verify that the Client ID and Client Secret entered in n8n are from that same Google OAuth client, that the Google People API/required Contacts API is enabled for the Google Cloud project, and that your Google account is permitted by the OAuth consent screen if the app is still in Testing mode. Save the Google configuration, save the n8n credential and reconnect it. If you previously attempted authorization with a different domain/configuration, start a fresh authorization attempt after redeploying rather than reusing the failed callback tab. The key diagnostic is the redirect URL: if the URL displayed by n8n and the Authorized redirect URI in Google Cloud are not character-for-character identical, correct that first. The “Insufficient parameters for OAuth2 callback” message is downstream of the OAuth flow failing; it is not normally fixed by changing the Google Contacts node itself.