thanks for your reply.
Exactly I don't know what has been done to the machine, maybe some installation too in order to improve security (it has been at customer's discretion). Certainly there is no internet connection at the moment (only local net) but all services run well.
I investigated a little more and I found an error in Hub Service Log: "Fatal error when starting the HubService ,Error: listen EADDRINUSE :::9028". So I think it's a problem on port 9028, which is listening, but (maybe) in use by another application. I exposed the situation to the customer and I'm waiting for a reply... there's something else I could take into account?