In a scenario where you have physically removed hardware from a machine you can no longer see it in device manager. This does not mean that it is gone. Evidence of that is, if for example you had a network card that had a Static IP address set and you remove the card and add a new one then try to set the IP address to the same as the old NIC you will get an error message. The error might look something like “The IP address 192.168.30.100 you have entered for this network adapter is already assigned to another adapter (Microsoft Virtual machine Bus Network Adapter #3) which is no longer present in the computer. If the same address is assigned to both adapters and they both become active, only one of them will use this address. This may result in incorrect system configuration”. In Windows Server 2008 R2 and Windows 7 it actually gives you an opportunity to “remove the static IP configuration for the absent adapter”. If you say Yes, this will eliminate the IP conflict problem but does not solve the problem of the adapter still being present in the machine. In older versions of the OS, it was even worse because every time you go into network properties it gives you an error message. Another way this comes up is if you move a virtual machine from one host to another. Like in the case of moving from Virtual Server 2005 R2 to Hyper-V or perhaps you are moving from one Hyper-V machine to another but you did not do an export, you just moved the VHD’s and created a new machine.
Getting rid of these old devices is actually very simple. Well, it is simple if you know how 😉
Before you proceed, I recommend that you confirm that you have a good backup. I have never had a problem with this but hey, it is your server not mine.
|Description||What to do|
|Step 1: You need to run a command prompt so you can set an environment variable prior to opening the Device Manager
This will bring up a command window
|Click Start – Type the following command and then press ENTER
|Step 2: We have the command window open. We now need to set the variable (that is the “set” line and then with the variable set, we need to run Device Manager. The file name for the Device Manager snap-in is devmgmt.msc. The first line will not appear to do anything but it is setting the environment for next step. The second command will actually open the Device Manager but it will be in a “special” mode which allows you to show devices that no longer exists.||Type the following commands pressing ENTER after each line
|Step 3: Now all we have to do is show hidden devices and you will be able to access the devices that are not present in the machine. This will also turn a checkbox on in front of the Show Hidden Devices menu option.||In this Special Device Manager Window; on the menu, click View then Show Hidden Devices|
|Step 4: Now you can just go find the adapter or device that is missing and delete it!
Expand the network adapter (or whatever category of device) and look for the device that needs to be removed. The error message that you got should tell you the “name” of the device so you just have to go find that named device. You may also notice while you are there that the icon for the “non-present” or missing device is slightly subdued so that will make it easier to find it if you have many devices in a category.
See screen shot below
|Expand the network adapter (or whatever category of device) and look for the device that needs to be removed.
Right-Click the Device and select Uninstall
It IS easy if you know how. Now you know how!!!
|On the Warning “You are about to uninstall this device from your computer” just click OK|
|IMPORTANT Note: Lastly, if there are other devices that are subdued / hidden, please to not just go in and delete them all. If you do, you are asking for trouble. Just get rid of the things that you know are gone for good and are not coming back! If you are not absolutely positive, do not remove it. If you do anyway, better have that backup handy
Also, remember, if you change too much stuff at once, you may have to reactivate Windows
|Restore from Backup… Just kidding|
T Man25 Sep 2010 5:53 PM
I also like setting the environment variable in system so I can view the hidden items anytime I want without having to set it manually.
Dumper8 Nov 2010 10:16 AM
Thank you! Great tip! Helped me removing some unused interfaces from a VM setup using kvm and Red Hat’s Virtio drivers.
André7 Jan 2011 2:41 AM
I’m having the same problem, but windows said: “Failed to uninstall the device. the device may required to boot up the computer” what i have to do???]
STRONG MAN10 Feb 2011 11:07 PM
How I can get lost network card setting ? for example IP address , Gateway , DNS settings . I need it to put on new card
— Not sure. The easy thing that comes to mind is check DNS on the network before you bring the server back up
Adrian31 Aug 2011 8:27 AM
thanks for your help. Worked like a charm
Lee from TX18 Oct 2011 6:24 AM
Good information, but one thing to note. I couldn’t see the hidden items if I went to Device Manager via Computer/Properties. I had to use the “start” method on the command line.