Read the rest of the hint for the how-to...
- Make sure that the printer is powered on and connected to the network via Ethernet, and is in the same IP range as your network. My network is using DHCP on 192.168.1.xxx, so I have assigned 192.168.1.248 to the Minolta as a static IP address using the menu on the printer.
- Reboot the Mac system if the printer was connected after the last reboot.
- Open the SDKColor.DMG file that you downloaded from Zenographics.
- Run the PKG file inside the DMG file. Complete the installation process. If no install hard drive appears, then click 'Back,' then click 'Next' again, you should then get a green arrow on the startup drive -- this happened to me.
- Open Print Center.
- Click the "Add" button while holding the ALT key.
- From the pop-up menu choose Advanced.
- From the second pop-up menu that appears, choose "AppSocket//HP JetDirect." You will then need to provide a meaningful name (eg Minolta Magicolor 2300DL) in the Device Name field below the menu. After that, insert the IP address of the printer after the text socket:// in the "Device URI" field below that -- for instance, mine reads socket://192.168.1.248.
- From the "Printer Model" pop-up menu, choose "ESP."
- From the list of models that appears below the Printer Model selection, choose the "Zenographics SDK Color CUPS v1.1" driver, then click the "Add" button at the bottom of the dialog.
[robg adds: An earlier hint contains another solution for the Minolta, though this one seems much simpler...]

