A service specialist from your company calls you from a customer's site. He is attempting to install an upgrade to the software, but it will not install; instead, it he receives messages stating that he cannot install the program until all non-core services are stopped. You cannot remotely access the machine, but the representative tells you that there are only four processes running, and their PID numbers are 1, 10, 100, and 1000. With no further information available, which command would you recommend the representative run?