This did show up a number of other USB devices including the malfunctioning serial driver (I deleted every USB device such as my mouse and webcam devices). Thanks for all your replies (I have just subscribed to the service and am very impressed).Sirbounty Comment:I had seen something like this from browsing Experts Exchange earlier today but I had forgotten to select View - Show Hidden Devices. Try removing hidden drivers in device manager and then reinstalling.Click Start-Run-CMDType the following lines exactly from the command prompt (misspelling won't generate an error):SET DEVMGRSHOWNONPRESENTDEV ICES=1START DEVMGMT.MSCIn the window that opens, Click View/Show all hidden devices.You should see ghost or transparent icons here that identify any drivers that have been left behind.Find your hardware and delete it from this list.Reboot and allow windows to reinstall the driver. Then the notebook refused to access the adapter as a serial interface. I have been using a Targus USB - Serial adapter (model PA088) on by laptop for some months.

Driver for targus pa088