Question 1

Install fails or Windows blocks the driver?

Accepted Answer

Run the WCH CH340 installer as administrator, use the latest signed package, and reboot. If it still fails, remove any older CH341SER/CH340 driver in Device Manager first.

Question 2

Device not detected / no COM port?

Accepted Answer

Try another USB cable and a direct PC port rather than a hub. In Device Manager, look for “USB-SERIAL CH340” under Ports or an unknown device; reinstall the driver and confirm the board is powered.

Question 3

Version conflicts or Code 10/yellow bang?

Accepted Answer

Uninstall the existing CH340 driver, select “Delete the driver software,” reboot, then install only the current WCH release. Avoid mixing CH340 and CH341 drivers from different sources.

WCH CH340 Driver