Before touching the installer, the device must exist in Estate Manager.
Device Maintenance
Navigate to EM > Device Maintenance and copy an existing device with similar settings. Give it a unique Device ID that exactly matches what will be entered in the installer.ini file (case-sensitive). The naming convention is:
pos1@LON001.enactor -- meaning POS 1 at location LON001 for company "enactor."
POS Terminal Maintenance
Navigate to EM > POS Terminal Maintenance and copy an existing terminal entry. Select the Device ID just created, give it a Terminal Name, and set the Terminal Number (usually the numeric part of the Device ID, e.g. "1" for pos1).