If a device is physically removed from the system before being uninstalled, the system will hide all settings from device manager. This can give a conflict when equel hardware is installed at a later point in time. To remove these “phantom” devices do one of the following steps:
1. Try running the temporary display as the Administrator, this way:
Click Windows Start > All Programs > Accessories and right-click Command Prompt, then “Run as Administrator”. Type “set devmgr_show_nonpresent_devices=1” and press Enter. Type “start devmgmt.msc” and press enter. Now in Device Manager click View > Show hidden devices.
2. To permanently display the “Phantom” devices in Device Manager, right-click Computer > Properties > Advanced System Settings > Advanced Tab > Environment Variables at the bottom. Click New and put devmgr_show_nonpresent_devices in the Variable Name and put 1 in the Variable Value and OK your way out.