Error in Sub-node 'MCP Client' Could not conect to your MCP server

Questions
1

Hi everyone,

I’m new to n8n cloud and I’m currently exploring its features. I ran into an issue when trying to use the MCP Client node. I’m getting the following error message:

Error in sub-node ‘MCP Client’
Could not connect to your MCP server

This is my first time working with n8n, so I’m not entirely sure how to troubleshoot this. I’ve double-checked the server URL and credentials, but the error persists.

Does anyone know what might be causing this issue or how I can resolve it?

Thanks in advance for any help!

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3 Likes
2

Same! Anyone solved this one?

3

@Zap_Flow instead of an image, it’s better if you pasted the actual code of the workflow. Select all nodes, copy, and paste it here in a code block (```…```)

Usually you won’t have any credentials in it, but make sure just in case.

4

me too , 请问这个问题解决了吗？没有设置任何的凭证

5

Im getting the same error. Did you figure it out? or someone else?

6

Here the same error, working with n8n Version 1.100.1 and n8n running in docker without any proxy all works fine (telegram too) now when I try to configure a mcp server I get the correct URL and checking with cursor it works fine. The issue is with the MCP client, I can´t see the MCP server. Any help please?

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7

Did you installed the MCP community node?

8

What do you mean with that? running with npm and ngrok works correctly

9

ah…
have you try to set your env for the webhook url?

10

Yes, this is my docker-compose file:

services:
n8n:
image: docker.n8n.io/n8nio/n8n:latest # Última versión disponible
container_name: n8n
restart: unless-stopped
ports:

  • “5678:5678” # Puerto público directo
    environment:

Configuración HTTPS

Configuración SSL con certificados externos

  • N8N_SSL_KEY=/certs/privkey.pem
  • N8N_SSL_CERT=/certs/fullchain.pem

Configuración de seguridad

  • N8N_SECURE_COOKIE=true
  • N8N_ENFORCE_SETTINGS_FILE_PERMISSIONS=true

Configuración de runners y proxy

  • N8N_RUNNERS_ENABLED=true
  • N8N_PROXY_HOPS=0 # Sin proxy

Configuración regional y técnica

  • GENERIC_TIMEZONE=Europe/Madrid
  • N8N_PUSH_BACKEND=websocket
  • N8N_PUSH_BACKEND_WS=true

Configuración adicional para HTTPS directo

  • N8N_LISTEN_ADDRESS=0.0.0.0

volumes:

  • ./n8n_data:/home/node/.n8n
  • ./n8n_export:/home/node/workflows_export
  • ./certs:/certs:ro # Certificados SSL externos en modo solo lectura
11

try to use localhost:5678 for the domain if you’re using localhost, and forward the port with ngrok

12

Yes, with npm an ngrok works correctly. But I would like with docker.

13

Maybe you can try to learn through this documentation
Using ngrok with Docker | ngrok documentation