During the installation process, if you are installing AcuConnect or AcuServer, you can choose to automatically start those services as part of the installation process.
Those services can only be started if certain conditions are met. For example, the services will attempt to start on a default port (AcuConnect 5632, AcuServer 6523). If an existing installation is already using that port, that service must be stopped if the installation is to create and run the new service. If you do not stop the existing service, the installation can only create the new service; it cannot run it.
If there is no previous installation, a default AcuAccess file is only created (in its default location of C:\etc) when the service starts. If you configure the installation to not start the service, no AcuAccess file will exist until you start the products from their respective control panels (or command line equivalents). If a previous installation exists, the AcuAccess file already located in C:\etc is used.