Connect to Target from GUI

Hi all,

I am trying to build a GUI for my model, I can build, activate, connect to target and run the model without problems, however when trying to do the same from the GUI at the time of connecting to the target I find all the time the same error (Error occurred while executing External Mode MEX-file 'ext_comm': Timed-out waiting for first connect response packet.) I can ping the Target and as I said connect to the target from the simulink model.

I am using the command set_param(handles.modelname, 'SimulationCommand', 'connect');

Any idea what is causing this?

Thank you.