When running 4D Server as a Windows Service, it is necessary to define any printers your 4D Server may need access to as 'Local Printers'.
But what about Networked Printers? Networked Printers can be defined as Local Printers also! To do this, you simply need to specify a TCP/IP port for the printer on your 4D Server machine. You can use the Printer Setup Wizard to accomplish this.
Without defining any networked printers as 'Local Printers' the Local System account will not have access to use them and, therefore, 4D Server cannot access them either when running as a Windows Service.
Use an administrator-type account when registering 4D Server as a service