The Close Process action allows you send a quit or a close message to a process running on the local machine.
To terminate an action outright, you can use the WMI Kill Process action.
Process
Specify the Process ID number of the process to close. The ID can be specified WMI Process Info actions.
Message
You can choose between sending the WM_QUIT or WM_CLOSE messages. The message will be sent to application's main window (you cannot close command line applications with this action - use WMI Kill Process instead.)
If WM_CLOSE is sent, the application will not pause for confirmation before closing.
"Terminate process if it has not ended..."
This option sets a timeout after which a process is forcibly terminated. This is useful if you would like to terminate a possibly unstable process, or a process which has paused waiting for confirmation of unsaved data (see WM_CLOSE in the Message section.)
If this option is not checked, the action will not pause to confirm whether or not the process has ended.