This article was previously published under Q315539
Device Manager displays only non-Plug and Play devices, drivers, and printers when you click Show hidden devices on the View menu. Devices that you install that are not connected to the computer (such as a Universal Serial Bus [USB] device or "ghosted" devices) are not displayed in Device Manager, even when you click Show hidden devices.
To work around this behavior and display devices when you click Show hidden devices:
Click Start, point to All Programs, point to Accessories, and then click Command Prompt.
At a command prompt, type the following command , and then press ENTER:
Type the following command a command prompt, and then press ENTER:
Troubleshoot the devices and drivers in Device Manager.
NOTE: Click Show hidden devices on the View menu in Device Manager before you can see devices that are not connected to the computer.
When you finish troubleshooting, close Device Manager.
Type exit at the command prompt.
Note that when you close the command prompt window, Window clears the devmgr_show_nonpresent_devices=1 variable that you set in step 2 and prevents ghosted devices from being displayed when you click Show hidden devices.
If you are a developer or power user and you want to be able to view devices that are not connected to your computer, set this environment variable globally:
To have us set the environment variable globally for you, go to the "Fix it for me" section. If you prefer to fix this problem yourself, go to the "Let me fix it myself" section.
Fix it for me
To fix this problem automatically, click the Fix it button or link. In the File Download dialog box, click Run, and then follow the steps in the Fix it Wizard.
After you run the package, you need click Show hidden devices on the View menu in Device Manager before you can see devices that are not connected to the computer.
This wizard may be in English only. However, the automatic fix also works for other language versions of Windows.
If you are not on the computer that has the problem, save the Fix it solution to a flash drive or a CD and then run it on the computer that has the problem.
NOTE: Use this method only for troubleshooting or development purposes, or to prevent users from accidentally uninstalling a required device that is not connected to the computer (such as a USB device or docking station that is not connected to a laptop computer).
Did this fix the problem?
Check whether the problem is fixed. If the problem is fixed, you are finished with this section. If the problem is not fixed, you can contact support.
We would appreciate your feedback. To provide feedback or to report any issues with this solution, please leave a comment on the "Fix it for me" blog or send us an email.
This behavior is by design.
In Device Manager, there are two types of hidden devices in addition to the devices that are displayed:
Typical, hidden devices that are not displayed (non-Plug and Play drivers, printers, and so on)
Phantom devices that are not connected to the computer