The Device is a Virtual Device Created by Software
Applies To: Windows Server 2008, Windows Vista
Software-only device drivers do not expose a device ID, and there is no standard method for installing these devices. Some manufacturers install the device by using the InstallShield installation program or a similar method. Note that software installed by other methods might not be completely removed when the device is removed in Device Manager, and therefore you might have to check the registry to verify that all entries are removed.
Diagnosis
Use any of the following methods to determine whether an unknown device was created by software:
Start your computer in Safe Mode. Although not 100-percent reliable, starting your computer in Safe Mode can be one of the easiest ways to determine whether the unknown device is created by software.
To start your computer in Safe Mode, press F8 after you restart your computer and before you see the Windows logo. On the Windows Advanced Option Menu, press the ARROW keys to select Safe Mode, and then press ENTER. If the unknown device is no longer listed in Device Manager, it is likely that the unknown device is not hardware.
Check the Startup folders. If you suspect that a specific program is the cause of the unknown device, check the Startup folders on your computer to see which programs are configured to start when your computer starts.
Your personal Startup folder is in the following location on your hard disk:
%appdata%\Start Menu\Programs\Startup
The All Users Startup folder can be found at:
%allusersprofile%\Microsoft\Windows\Start Menu\Programs\Startup
Note
You must have administrator privileges to modify items in the All Users Startup folder.
Use the System Information tool. The System Information tool can be useful when you need to identify the cause of an unknown device.
To use the System Information tool to view a list of programs that start when your computer starts, follow the steps in the procedure Use MSInfo32 to view the list of startup programs.
To use the System Information tool to view a list of problem devices, follow the steps in the procedure Use the System Information tool to view a list of problem devices.
View the Setupapi.log file. If the device has a meaningful name, use the information in the Setupapi.log file to identify the cause of an unknown device. By default, the Setupapi.log file is located in the %systemroot% folder.
Sometimes the list designation can be misleading. For example, a device might be listed as a serial device in Device Manager, when in reality it is not related to a serial port. This typically occurs when a partial Plug and Play ID is available, and Device Manager interprets it as a serial device. This can also be corrected by locating the startup program.
Removing an unknown device in Device Manager does not resolve the error if a software program is the cause of the unknown device. You must remove the program, and then restart your computer. If the unknown device is still listed in Device Manager after you restart your computer in Safe Mode, refer to your hardware manufacturer documentation for help in removing the device.
Resolution
Use MSInfo32 to view the list of startup programs
To use MSInfo32 to view the list of startup programs
Click Start, and then in the Start Search box, type msinfo32, and press ENTER.
In the navigation pane, expand Software Environment, and then double-click Startup Programs.
A list of the programs that are configured to start when your computer starts is displayed.
Check the event log for errors that refer to any of these programs. Note that when a program creates an unknown device, the program can work unless it depends on that device to start.
Use the System Information tool to view a list of problem devices
To use the System Information tool to view a list of problem devices
Click Start, and then in the Start Search box, type msinfo32, and press ENTER.
In the navigation pane, expand Components, and then double-click Problem devices.
A list of the devices installed on your computer that might have a problem is displayed in the right pane, as follows:
The Device column lists the common name for the device, or the name of the device driver associated with it.
The PnP Device ID column lists device IDs, such as a Peripheral Component Interconnect (PCI) ID, an Industry Standard Architecture (ISA) ID, an ID for some other bus type, or an unknown type.
The Error Code column lists the error code associated with this specific problem. In many situations, the Device Manager error code helps determine what created the unknown device. For example, if your computer generates a Bad or missing device driver error message, three types of error codes might be listed under Problem Devices, depending on the device type:
PCI PnP Device ID
Device Name | PCI\VEN_00000&DEV_0000&SUBSYS_00000000&REV_00\0&0000 | Error code
ISA PnP ID
Device Name | ?\PNP0000\0
Bad or Incompatible Device Driver
Device Name | ROOT\UNKNOWN\0000
For more information about specific error codes, see Error Codes in Device Manager.