FAQ# 2418: My Star Printer, TSP100IIIU is not recognized by Square.

Answer

If your brand new Star USB printer for Square does not work, chances are your device was preconfigured in a different mode such as "GX Mode." Follow the steps below to see if your printer has been preconfigured to a different mode and how you can get it working again:

1. Open the paper cover, press and hold down the FEED button while turning the printer ON.
2. Keep holding the FEED button for 5 seconds until the LED lights start flashing rapidly in an alternating pattern.
3. Release the FEED button to enter “Special Mode” (Power light ON, Error light OFF).
4. While the printer is ON, press the FEED button to cycle through the LED codes until the Power light is ON and the Error light is OFF. Although the lights may already be set to Power light ON and Error light OFF, it is critical to cycle through the codes to ensure the correct setting mode is activated.
5. Close the paper cover to confirm the setting mode:
   1. If done successfully, the printer will display the Power light flashing rapidly with the Error light OFF, indicating the Old model compatible PID setting mode.
6. Once in the correct LED code, open the paper cover again, press the FEED button, and the LED lights will start flashing alternately once per second.
7. Turn the printer OFF, wait for 10 seconds, and perform a self-test to confirm the successful setting change.