After updating chipset drivers, repeat Fix 4 (reinstall Focusrite driver).
Common triggers include:
Unplug the USB cable from the back of the Focusrite interface. cannot open focusrite usb asio error code 0x54f
Windows reassigns a fresh driver stack and resets the USB enumeration. Error 0x54f often disappears immediately after this. After updating chipset drivers, repeat Fix 4 (reinstall
Before diving into the fix, it is helpful to understand the terminology. After updating chipset drivers