Moxa USB Serial Port (COM20) Driver

The Moxa USB Serial Port (COM20) driver allows Windows to communicate with compatible Moxa USB-to-serial hardware through a virtual COM port. It helps applications exchange data with connected serial equipment, including printers that use a serial interface, rather than treating the adapter as an unrecognized USB device.

Key Features

• Virtual COM port access: Makes compatible Moxa hardware available to software that communicates through a standard Windows serial port.
• Serial communication settings: Allows supported applications to use settings such as baud rate, parity, data bits, and flow control to match the connected equipment.
• Hardware recognition: Helps Windows identify the USB-to-serial adapter and display its serial interface under Ports (COM & LPT) in Device Manager.
• Windows driver options: Use the package intended for your exact Moxa model and Windows 11, 10, 8, or 7 installation, checking model-specific compatibility before downloading.

How to Install

1. Identify your Moxa hardware. Check the model number on the adapter or its label. “Moxa USB Serial Port (COM20)” is a Windows port description; it may not identify the exact hardware model needed to choose a driver.

1. Select the matching package. Confirm that the driver supports your device and Windows version. Check whether your system requires a 32-bit or 64-bit package, and read any included installation instructions.

1. Install the driver. If the download is compressed, extract it first. Run the supplied installer with administrator permission and connect the adapter when prompted. If no installer is provided, use Device Manager’s Update driver option and browse to the extracted driver folder.

1. Verify the port assignment. Open Device Manager and expand Ports (COM & LPT). Confirm that the Moxa serial interface appears without a warning icon. Windows may assign COM20 or another available port number.

1. Configure and test your application. Select the assigned COM port in your printer utility or other serial software, then match the communication settings to the connected device. Restart Windows if the installer requests it.

For a serial printer, this driver provides the communication link through the Moxa adapter; the printer may also require its own driver or application setup. If software cannot open COM20, check that another program is not already using it and that the application supports that port number.

Common Issues and Fixes

• Install fails or rolls back: Disconnect the Moxa USB serial adapter, run the Moxa installer as administrator, and reboot before reconnecting. Use the signed driver package matching your Windows version and architecture.
• Device not detected / COM20 missing: Check Device Manager for an unknown USB device or yellow warning. Try another USB port and cable, uninstall any broken entry, then rescan. Confirm the driver supports your exact Moxa adapter model.
• Version or COM-port conflicts: Remove old Moxa driver versions and stale COM assignments using Device Manager’s hidden devices. Install the current Moxa driver, then reassign COM20 if another device occupies it. Avoid mixing the Windows generic serial driver with the Moxa driver.