Ensure the printer is connected via but remains turned OFF . Run the downloaded .exe driver installer.
| Symptom | Likely Cause | Fix | | :--- | :--- | :--- | | | Bad USB cable or USB port | Try a different cable; use a USB 2.0 port (not 3.0). | | Prints gibberish/symbols | Wrong driver language (PCL instead of ESC/POS) | Switch to the "Generic / Text Only" driver as a test. | | Paper feeds but no text | Paper loaded upside down | Thermal paper has a shiny side. Re-roll the paper. | | Prints half page then jams | Paper size mismatch | Set paper size in Print Server Properties to custom 80mm. | ngx tp 300 thermal printer driver download top