Troubleshoot Receipt Printer Usage on Windows

Use this guide when a Windows POS computer can see a USB receipt printer, but Storepass cannot print directly to it. Common signs are Chrome opening the normal print dialog, the printer not appearing in the browser device picker, or a test receipt printing unreadable output.

Windows and Chrome often need an extra WinUSB/libusb driver layer before they can talk to USB receipt printers the same way Apple and Linux devices usually can. This setup is done once per printer on each Windows computer and normally does not need regular updates.

• Use this for USB receipt printers connected to a Windows POS computer.
• Use this when direct Storepass receipt printing falls back to the browser print dialog.
• Use this after the printer has already been installed using the printer manufacturer's instructions.

Before starting

1. Plug in all USB receipt printers and any cash drawers connected through those printers.
2. Install the printer manufacturer's Windows drivers and setup software according to the printer manual.
3. Open Storepass in Chrome or Edge on the Windows POS computer.
4. Go to the receipt printer debug page in Storepass, connect the printer, and run a test print.

If the browser print dialog opens, the printer cannot be selected, or the test receipt prints as unreadable characters, install the WinUSB driver with Zadig.

Download Zadig

1. Go to zadig.akeo.ie.
2. Download the current Zadig .exe from the Downloads section.
3. Open the downloaded file. If Windows asks for permission to run it, allow it.

Configure the printer driver

1. In Zadig, open Options and select List All Devices.

1. Use the device dropdown to choose the receipt printer. It may appear as the printer model, such as TM-T20III, or as a generic name such as POS80 Printer USB.

1. Select WinUSB (Microsoft) as the driver. If WinUSB is already selected, that is okay.
2. Click Install Driver, Replace Driver, or Reinstall Driver, depending on which button Zadig shows.

1. Wait for Zadig to finish, then close the success message.

Only change the driver for the receipt printer. Do not select a webcam, Bluetooth radio, keyboard, mouse, scanner, or another unrelated USB device.

Use Storepass again

1. Reload the Storepass receipt printer debug page, or close and reopen Chrome or Edge.
2. Select the printer again from Storepass.
3. Run another test print.
4. If the cash drawer connects through the printer, test the drawer after receipt printing works.

Review and monitor

• Works after WinUSB: Use the POS normally. The browser should remember the printer grant after it is selected.
• Still opens the print dialog: Make sure the POS is using Chrome or Edge, reload Storepass, and select the USB printer again from the receipt printer debug page.
• Printer is not listed in Zadig: Confirm the printer is powered on, connected by USB directly to the Windows computer, and that Options > List All Devices is enabled.
• Printer disappears after a Windows or vendor update: Repeat the Zadig steps for that printer.
• Output is still unreadable: Confirm the selected device was the receipt printer. If needed, unplug unrelated USB devices temporarily and repeat the selection step.

After setup

Once the printer prints correctly from Storepass, no regular Zadig maintenance is needed. Repeat these steps only when adding a new USB printer, moving the printer to a different Windows computer, or after a driver update changes how Windows exposes the printer.