AutomateLab

n8n errors / Connectivity

unable to verify the first certificate

platform: n8n / category: Connectivity / code: UNABLE_TO_VERIFY_LEAF_SIGNATURE

Cause

The server's TLS chain is incomplete - the leaf cannot be traced to a trusted root because intermediate certificates are missing.

Fix

Fix is server-side: configure the web server to serve the full chain including intermediates. Temporarily enable 'Ignore SSL Issues' in the node to confirm the cause. Verify with 'openssl s_client -connect host:443' and look for 'verify error'.

Source thread →

Part of the Automation Error Index — n8n errors: browse all.

Hitting an automation error we have not covered?

AutomateLab builds and debugs n8n, Make, and agent workflows as fixed-scope projects. If something is broken in production, tell us what you are seeing.

Describe the problem