When you buy a TestStand runtime license, all you get is a piece of paper with a serial number on it. For TestStand 3.0, when you install the runtime engine, it will ask for a serial number. Use the serial number that comes with your new license. The registration process will give you the computer ID of the machine you are installing it on. Then you must register that serial number and computer ID with NI, and you will get an activation code in return. When running the TestStand runtime engine on the new computer, you will be asked for this activation code. Enter it and you can use TestStand runtime without limitation. Without the code, you can run TestStand Evaluation version for 30 days and it will limit your running time to 10 minutes per session.