How to deactivate safety system to run simulation?


I am trying to simulate RAPID program on Robotstudio, which works error-free with real robots. 

However, the simulation doesn't work with the following errors:
90541: Superior Stop opened by the Safety Controller
90518: Safety Controller Emergency Stop triggered
90523: Safety Controller Protective Stop triggered

So I disabled safety signals using I/O simulator and the following error occurred:
The operation is not allowed by the safety system. The event log may contain more information.

No useful event log was provided and I have no Idea how to let the simulation run.