No EtherCAT connection

This is one of the most common errors. It can be caused by multiple factors. Most common are listed below.

Hardware

Robot is turned off

Devices that are turned on usually works better.

Wrongly connected Ethernet cable

Proper cable connections are shown on a page Connecting youBot to external computer

Internal PC is turned on

When you want to control KUKA youBot with an external PC you have to be sure that internal PC is turned off.