ok i've got a driver cd that came with that device here is its content E:\Usb To Rs232\XCS-232-340 -340.exe ##which is self-extracting rar file ----it contains 5 files in it : setup.exe , USBSER34.INF , USBSER34.SYS , USBSER34.VXD , USBSER98.INF E:\Usb To Rs232\XCS-232-2303 -PL2303 driver.exe ##installation wizard file -remove old driver.exe -ser2pl.sys -ser9pl.sys -serspl.inf -serspl.vxd -serwpl.inf what i do is installing content of first folder then installing pl2303 driver. to get it work on my windows desktop i hope this helps i can send content of any file above if it helps