Help getting a USB serial device working on Ubuntu Linux

We have a USB device that connects and works perfectly as a serial device on Windows. It identifies as a comm port and we can communicate with it perfectly. However, presumably because the VID:PID are not recognised it is not identified by Linux as a USB Serial device. The answer probably lies in forcing USB Serial to identify this VID:PID pair as a Generic Serial device as found at [login to view URL] [login to view URL] This did not appear to immediately work echo <vid> <pid> >/sys/bus/usb-serial/drivers/generic/new_id and I was not able to load the module insmod usbserial vendor=0x#### product=0x#### gave insmod: ERROR: could not load module usbserial: No such file or directory usb-devices shows that there is no loaded module. T: Bus=01 Lev=02 Prnt=02 Port=04 Cnt=02 Dev#= 4 Spd=12 MxCh= 0 D: Ver= 2.00 Cls=02(commc) Sub=00 Prot=00 MxPS=64 #Cfgs= 1 P: Vendor=XXXX ProdID=YYYY Rev=01.00 S: Manufacturer=XXXXXXXXXXXXXX S: Product=RetroFreak PCB-B S: SerialNumber=0123456789AB C: #Ifs= 2 Cfg#= 1 Atr=c0 MxPwr=100mA I: If#= 0 Alt= 0 #EPs= 1 Cls=02(commc) Sub=02 Prot=01 Driver=(none) I: If#= 1 Alt= 0 #EPs= 2 Cls=0a(data ) Sub=00 Prot=00 Driver=(none)