Hi,
I just make a nice hack. I get a lot of Arduino nano for 67 Cent from China.
They work under Win10 but not under XP SP3, "Unknown USB device".
I use the Arduino IDE ver. 1.8.9 portable, means no installation.
It has the exotic USB serial VID_0843&PID_5740.
So, I take the win7 driver STM32_vcp_driver.zip from STMicroelectronics which has funny VID_0483&PID_5740.
There I edit just the stmcdc.inf file only at this part
;------------------------------------------------------------------------------
; VID/PID Settings
;------------------------------------------------------------------------------
[DeviceList.NT]
%DESCRIPTION%=DriverInstall,USB\VID_0843&PID_5740
[DeviceList.NTamd64]
%DESCRIPTION%=DriverInstall,USB\VID_0843&PID_5740
Right click on this modded stmcdc.inf "install",
and voila, this Arduino nano clone from China works perfect under XP SP3
Dietmar