The UB-U03II driver did not install correctly. Fix:

: This card is compatible with a wide range of TM-series printers, including: Thermal Printers : TM-T88IV, TM-T88V, TM-T70. Impact/Dot Matrix : TM-U220, TM-U590, TM-U230. Multifunction : TM-H6000 series. Installation Guide for Windows 10

To get the UB-U03II working on Windows 10, you generally do not search for a "UB-U03II driver." Instead, you must install the Epson Advanced Printer Driver (APD) for the specific printer model. Spiceworks Community Identify the Printer

Always download the 64-bit driver if your Windows 10 is 64-bit. It handles USB data streams faster than 32-bit.

: Turn the printer off, hold the "Feed" button, and turn it back on. It will print a self-test page listing the exact model (e.g., TM-T88IV). Download Official Software : Visit the Epson POS Support Page to download the latest (typically version 5 or 6) for your model. Port Configuration

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