do you have Administrator rights for the machine in question? If not then you'll need to switch to an account that has administrative rights for the machine.
Also, the screenshot shows the Configuration menu for a Scheduling server. If you need to setup the machine as an Execution Server (and you have a Scheduling server setup on a different machine) you won't need to access that menu. Instead you need to start the Execution Server configuration app and configure that. If you haven't done so already please check out the section on Scheduling in our user's guide:
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