Windows Arduino Nano Arduino Uno clone CH341

CH341 driver download for Arduino (Windows)

If your Arduino clone board is not being recognized by Windows, you are most likely missing the CH341 USB-to-serial driver. Download it below and follow the installation steps.

CH341SER driver Windows

Free. Safe. No account required. Windows may show a security warning on install, this is normal.

Download CH341 Driver

Do you have this problem?

If any of the following apply, the CH341 driver is most likely the fix:

You are using an Arduino Nano, Uno clone, or ESP8266 board
No serial port appears under Tools → Port in the Arduino IDE
You see one of these error messages when uploading:

avrdude: ser_open(): can't open device "\\.\COM3": The system cannot find the file specified.

avrdude: stk500_recv(): programmer is not responding

avrdude: ser_open(): can't open device: No such file or directory

Why does this happen?

Arduino clone boards use a CH340 or CH341 chip to handle USB-to-serial communication. Official Arduino boards use a different chip that Windows recognizes automatically. Clone boards, which are cheaper and very common require you to install the CH341 driver manually before Windows can communicate with the board.

How to install the CH341 driver

Download the driver

Click the download button above to save CH341SER.EXE to your computer.

Run the installer

Double-click CH341SER.EXE to open the installer. If Windows shows a security warning, click Run anyway the file is safe.

Click Install

In the installer window, click Install and wait for the confirmation message.

Reconnect your board

Unplug your Arduino board and plug it back in. Windows will now recognise it.

Restart the Arduino IDE

Close and reopen the Arduino IDE. Your board's COM port should now appear under Tools → Port.

Still not working?

Try a different USB cable. Many cheap USB cables are charge-only and do not carry data. This is one of the most common causes of the board not being detected even after the driver is installed.

Windows 11 sometimes blocks unsigned drivers. Right-click CH341SER.EXE, select Properties, go to the Compatibility tab, and run the installer as administrator. Alternatively, open the installer, select Uninstall first, then reinstall.

Make sure the correct board is selected under Tools → Board. For an Arduino Nano clone, select Arduino Nano and set the processor to ATmega328P (Old Bootloader) most clones use the old bootloader.

This driver is for Windows only. On macOS, download the CH34x driver from the manufacturer. On Linux, the CH341 driver is usually built into the kernel, try plugging in the board and running dmesg | grep ch341 in terminal to confirm it is detected.

Driver installed? You are ready to upload your first sketch.

Head back to the Hello World lesson to continue setting up your Arduino IDE and write your first program.

Continue to Hello World lesson