I use find_system in my Matlab script to find a library block in my simulink model, which I tagged (find_system('model', 'tag' ,'tag_name'). This works nicely, however, when I open the model using my script and then execute find_system, it does not get the handle constantly. Sometimes it does, sometimes it doesnt. When I once run the model, its ok. However, this is not a good solution. I really need to open the model and then execute find_system right away. Does anyone know, why find_system does not work properly in this case and what I can do?