CH340 Driver Installation Failure – Troubleshooting Guide

## I. For Windows Systems

### 1. Common Causes & Solutions

**1) System Compatibility Issues**

* Windows 10/11 usually have built-in drivers, but auto-installation may fail.

* **Solution:** Manually download the latest driver from the official site (e.g., [wch.cn](http://www.wch.cn))—file name **CH341SER.EXE**.

**2) Old Driver Conflicts**

* Previously installed CH340/CH341 drivers may block installation.

* **Solution:**

  * Open **Device Manager → View → Show Hidden Devices → Ports (COM & LPT)**.

  * Right-click and **uninstall all CH340/CH341 devices, and check “Delete the driver software for this device.”

  * Reinstall the latest driver.

**3) Driver Signature Issues (Win7 / Some Win10)**

* The system blocks unsigned drivers.

* **Solution:**

  * Restart PC → Advanced Startup → Select **Disable Driver Signature Enforcement**.

  * Then run the installer.

**4) Insufficient Permissions**

* Administrator rights are required.

* **Solution:** Right-click → **Run as Administrator**.

**5) USB Cable/Port Problems**

* Charging-only cables cannot transfer data; the device won’t be recognized even if the driver installs.

* **Solution:** Use a data-capable USB cable, preferably directly into a USB 2.0 port.

---

### 2. Confirm Successful Installation

* Plug in the device → Open **Device Manager**.

* Under **Ports (COM & LPT)**:

  * If you see **USB-SERIAL CH340 (COM3)**, installation succeeded.

  * If there’s a yellow exclamation mark → driver failed or conflicts exist.

---

### 3. Alternative Solutions

* Try another computer to rule out system issues.

* Use an **FT232 / CP2102 USB-to-Serial adapter** as a hardware workaround (better compatibility).

---

## II. For macOS Systems

### 1. Check if a Driver is Needed

* macOS 10.13+ sometimes recognizes CH340 chips automatically.

* Plug in the device → open **Terminal**, enter:

```bash

ls /dev/tty.*

```

* If you see something like `/dev/tty.wchusbserial1410` → no driver installation needed.

### 2. If Not Recognized → Install Driver

**1) Download Driver**

* Official: [CH341SER_MAC_ZIP](https://www.wch.cn/downloads/CH341SER_MAC_ZIP.html)

* Recommended open-source version: [GitHub – wchusbserial for macOS](https://github.com/adrianmihalko/ch340g-ch34g-ch34x-mac-os-x-driver)

**2) Allow Kernel Extension**

* macOS may block installation (“System Extension Blocked”).

* **Solution:**

  * Open **System Preferences → Security & Privacy → General**

  * Click **Allow** for **WCH Electronics Co., Ltd.**

**3) Restart Computer**

* Must restart after installation to load the driver.

---

## III. Common Troubleshooting

1. **Driver installed but port not found**

* In Terminal, enter:

```bash

ls /dev/tty.*

```

* Re-plug the device to see if a new port appears.

2. **M1/M2 Mac (ARM)**

* Official drivers are often Intel-only; they may be incompatible.

* Use the open-source driver (GitHub – adrianmihalko version) for better compatibility.

3. **Permission Issues**

* Newer macOS versions (Big Sur / Monterey / Ventura) have stricter third-party driver policies.

* If there is no “Allow” option in Security & Privacy:

  * Reboot into **Recovery Mode**

  * Disable **System Integrity Protection (SIP)**, then install the driver.

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## IV. Alternative Solutions

* Use an **FTDI USB-to-Serial adapter** (macOS native support, no driver needed).

* Or connect via **Wi-Fi** if your GRBL board supports it.

---