This trick will force Windows 2000 or XP to show you any unused or double-installed drivers.

USB drivers installed correctly but cannot see audio or MIDI ports in recording software. The problem is caused by a 10 USB driver limitation in Windows XP/2000.

Click on "Start" and choose "Run," then type in "cmd" as the command line. Click "OK" and a DOS prompt will open. Type the following commands one line at a time, hitting enter after each:

set devmgr_show_nonpresent_devices=1
start devmgmt.msc

The Device Manager will now open up, so click on the View menu and choose "Show Hidden Devices."

Look through the device manager carefully and note that there are a lot of drivers with a kind of translucent colored icon next to them. These are what are called "ghosting" or otherwise nonpresent drivers your computer is remembering in case you were to ever use the device again later. They can also be drivers that do system functions and are hidden by default, or partially installed or corrupted driver install attempts, all sorts of things really.