Hi Felix,
In order for the MATLAB not to be busy, you have to close the program and then you can resume to work in MATLAB.
There's also an option that tells MATLAB not to wait for the program to be closed if you add the '&' symbol.
cmd = 'C:\...\_exe &';
system(cmd)
However, you should be (this is useful if you want to interact with simulation settings etc.) working with external API for ANSYS through the COM server. See actxserver function and documentation on API in ANSYS.
