If you absolutely need SpeedFan for a legacy project (e.g., an industrial PC running Windows 7), use Method 2 or 3. For everyone else on Windows 10/11, uninstall SpeedFan, download Fan Control, and enjoy silent, cool computing without the driver nightmare.

This setting resets after every normal reboot. You must repeat the process or move to Method 3.

SpeedFan hasn't been updated in years and is no longer actively developed. It uses a legacy driver (

This is not a bug. It is a security feature of modern Windows clashing with legacy software.

This is the most common fix for the "SpeedFan driver not installed" error. It allows Windows to load the unsigned driver.

If you are willing to lower security permanently (not recommended for laptops or work PCs), use this method.