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Windows 11 can often install the CH340 driver automatically through Windows Update. If it does not, install WCH’s official CH341SER.EXE package, then verify that the adapter appears under Ports (COM & LPT) as a device such as USB-SERIAL CH340 (COM3).
The CH340 and CH341 are USB-to-serial chips used in Arduino-compatible boards, ESP development boards, USB-to-TTL adapters, and other electronics hardware. The correct driver depends on the chip actually fitted to the device, not just the product’s name.
Before installing the driver
Connect the board or USB-to-serial adapter to the PC and open Device Manager:
- Open Start.
- Type Device Manager.
- Select Device Manager from the results.
Look under Other devices, Unknown devices, or Ports (COM & LPT). A device with a warning icon may be listed as an unknown USB device or as a USB serial device without a usable driver.
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To check whether it really uses a WCH CH340-family chip, right-click the device, select Properties, open the Details tab, and choose Hardware Ids from the property list. A CH340-family device commonly has vendor ID VID_1A86. If the ID is VID_0403, for example, it is associated with FTDI hardware and requires an FTDI driver instead.
Method 1: Let Windows 11 install the CH340 driver
This is the simplest and safest method when the device is detected correctly.
- Connect the CH340 board or adapter directly to the computer.
- Make sure the PC is online.
- Wait several seconds for Windows Update to search for a compatible driver.
- Open Device Manager and expand Ports (COM & LPT).
- Look for an entry such as USB-SERIAL CH340 (COMx) or USB Serial Port (COMx).
Microsoft Update Catalog currently lists WCH driver version 3.9.2024.9, dated September 16, 2024, for Windows 11 Client version 22H2 and later. The listing supports devices identified as USB-SERIAL CH340, USB-SERIAL CH341, USB-SERIAL CH340K, and USB-SERIAL CH330. The listed architecture is AMD64.
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1Fix the driver behind crashes, sound loss and screen glitches2Repair Windows errors before they cause bigger problems3Scan for outdated or missing drivers - takes under a minuteThe number represented by COMx is not fixed. Your device might appear as COM3, COM5, COM7, or another available port. Applications such as Arduino IDE normally require you to select that exact port from their Tools > Port menu.
Method 2: Install WCH’s official driver manually
Use this method if Windows Update does not install a driver, Device Manager still shows a warning icon, or you need to reinstall the package.
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1. Download the official package
Download CH341SER.EXE from WCH, the chip manufacturer. WCH describes this as its CH340/CH341 USB-to-serial VCP driver and lists support for Windows 11, Windows 10, Windows 8.1, Windows 8, Windows 7, Vista, XP, 2000, and 98, including 32-bit and 64-bit systems. WCH also states that the driver is Microsoft WHQL/HCK certified.
Do not assume that every file named CH341SER.EXE on a download site is the current package. The Microsoft catalog explicitly identifies version 3.9.2024.9; WCH’s download page identifies the package by filename and supported systems but does not, in the retrieved page content, confirm that version number.
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2. Run the installer
- Open the downloaded
CH341SER.EXEfile. - Follow the installer prompts to install or pre-install the driver.
- Restart Windows if the installer requests it.
- Disconnect and reconnect the CH340 device.
The installer may say that the driver was successfully pre-installed even when no CH340 device is connected. This means Windows received the driver package; it does not prove that the board is detected or that a COM port exists. Verify the result in Device Manager with the device connected.
3. Bind the driver through Device Manager if necessary
- Open Device Manager.
- Right-click the CH340 device. It may be under Other devices, Unknown devices, or Ports (COM & LPT).
- Select Update driver.
- Choose Browse my computer for drivers.
- Browse to the extracted WCH driver folder containing the
.inffile. - Enable Include subfolders.
- Select Next and allow Windows to install the matching driver.
After installation, unplug and reconnect the board. Check for USB-SERIAL CH340 (COMx) or USB Serial Port (COMx) under Ports (COM & LPT).
If no COM port appears
A successful driver installation and a working serial connection are separate things. Work through these checks in order:
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- 【Standard Pins, Simplifying Connections】 The board has RX/TX/VCC/GND pins with clear markings. Connect the module’s TX→device RX, RX→device TX, share GND, and select 5V/3.3V for VCC—steps familiar to users of a USB to Serial Converter or USB to TTL Adapter. Simple wiring quickly establishes communication, lowering development/debugging barriers. This plug-and-play design mirrors the ease of a basic usb to ttl tool, streamlining integration.
- Try another USB cable. Many inexpensive cables provide charging only and have no data wires.
- Use another USB port. Connect directly to the computer instead of through a hub or docking station.
- Reconnect the board while Device Manager is open. The device list should refresh or change when the hardware is attached.
- Check the hardware ID. Confirm that the device has a CH340-family ID such as
VID_1A86. - Test another computer. This helps distinguish a Windows configuration issue from a defective board or cable.
If Device Manager reports Unknown USB Device (Device Descriptor Request Failed), Windows has not successfully enumerated the hardware. A driver reinstall may not fix this condition. The cable, USB port, hub, board power, or the USB interface itself may be faulty.
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Cleanly remove and reinstall the driver
Use a clean reinstall when the device previously worked but now shows a driver error, or when Windows is binding an incompatible package.
- Open Device Manager.
- Right-click the CH340 device and select Uninstall device.
- If Windows shows Delete the driver software for this device, select it when you need to remove the associated package completely. This option may not appear for every device.
- Select Uninstall.
- Restart Windows.
- Reconnect the device and let Windows Update reinstall it, or run WCH’s installer again.
Microsoft also documents an alternative reinstall path: after uninstalling the device, open the Device Manager menu and select Action > Scan for hardware changes. Windows will detect the hardware again and may reinstall its driver.
Fix Code 31 and Code 32
Code 31
Code 31 means Windows cannot load the drivers required for the device. The message is typically:
This device is not working properly because Windows cannot load the drivers required for this device. (Code 31)
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In Device Manager, right-click the device, choose Update driver, and reinstall the WCH package using the manual process above. If that does not work, remove the device and its removable driver package, restart Windows, and install it again.
Code 32
Code 32 indicates that a driver service has been disabled or that another driver may be taking precedence. The recovery sequence is:
- Right-click the device in Device Manager.
- Select Uninstall device.
- Open Action > Scan for hardware changes.
- Reconnect or reinstall the CH340 driver if Windows does not restore it automatically.
Do you need the old 2019 CH340 driver?
Usually, no. Windows 11 does not universally require a 2019 CH340 driver. The current Microsoft catalog listing for Windows 11 22H2 and later is WCH version 3.9.2024.9. Older packages, including 3.8.2023.2 and much older entries dated November 3, 2011, remain visible in the catalog, but their presence does not make them the preferred Windows 11 driver.
A particular board, application, or driver-binding problem may justify testing an older compatible package, but start with Windows Update or the current WCH package. Avoid downloading an unverified “2019 driver” from a third-party site merely because a guide recommends it.
What success looks like
| Device Manager result | Meaning |
|---|---|
| USB-SERIAL CH340 (COMx) | The CH340 driver is installed and Windows has assigned a serial port. |
| USB Serial Port (COMx) | A compatible USB serial driver is installed; note the assigned COM number. |
| CH340 under Other devices with a warning icon | The hardware is detected, but the driver is missing or has not been bound. |
| Unknown USB Device | USB enumeration has failed; investigate the cable, port, power, hub, or hardware before repeatedly reinstalling drivers. |
| Driver pre-installed, but no device listed | The package is staged in Windows, but no connected CH340 device has successfully created a COM port. |
FAQ
Does Windows 11 install the CH340 driver automatically?
Often it does through Windows Update. Microsoft Update Catalog currently lists WCH driver version 3.9.2024.9 for Windows 11 22H2 and later. If no COM port appears, install WCH’s official CH341SER.EXE package manually.
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- √Installation Instructions: 1. Run the driver CH340.EXE file to install 2. Connect the USB serial cable to the USB interface of the computer, and automatically install the driver 3. After the installation is successful, the COM port appears in the device manager
Where is the CH340 COM port in Windows 11?
Open Device Manager and expand Ports (COM & LPT). A working device may appear as USB-SERIAL CH340 (COMx) or USB Serial Port (COMx). The number varies between computers and USB ports.
Why does the installer say the driver was pre-installed but no COM port exists?
Pre-installation only places the driver package in Windows’ driver store. It does not confirm that a board is connected, that the cable supports data, or that USB enumeration succeeded.
How can I tell whether my adapter is really a CH340?
In Device Manager, open the device’s Properties, select the Details tab, and choose Hardware Ids. CH340-family devices commonly use vendor ID VID_1A86. A different ID may indicate another chipset.
Should I install a 2019 CH340 driver on Windows 11?
Not as a general rule. Begin with Windows Update or the current WCH package. An older driver may be a workaround for a specific compatibility problem, but it is not a universal Windows 11 requirement.
The Bottom Line
Start by connecting the device and allowing Windows Update to install the driver. If that fails, download WCH’s official CH341SER.EXE, run it, and use Device Manager’s Update driver > Browse my computer for drivers option if Windows does not bind the package. Confirm success only when the connected hardware appears under Ports (COM & LPT) with a COMx number. If it remains an unknown USB device, troubleshoot the cable, USB port, power, and hardware rather than treating every enumeration failure as a driver problem.
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