Failing to Launch Application in Rancher

Hello Folks,

I am working in Rancher web interface, I am trying to launch an application and i get this error:

failed: error during WebSocket handshake: unexpected response code: 400


Can you provide more details of your setup?

Rancher Version, Docker Version, OS of hosts

What is your setup? Vanilla install? Using external DB? Is rancher/server on its own machine or not?