Hi Liu, 

Couple of questions: 

- What operating system are you using? 
- Did you try running DKE using the command line?

Lastly, just so you know we are phasing out support for DKE and have moved to a different processing software that will be more active. I will post the link here for your convenience: https://pydesigner.readthedocs.io/en/latest/ 

Best, 
Emilie