When you run a file or project, the server tools first verify that the servers and configurations for that particular resource are already set up and determines how many are defined. You are then prompted by the Run on Server dialog box to select a server.
If this is the first time you are testing a file or project, you will be prompted to create a new server. The Run on Server dialog box presents you with two options for deciding which server to run:
If this is the first time you are testing a file or project, Manually define a server is selected for you by default. When you select the type of server and click Next, a server will be automatically created for you and the server will start.