Most people using Windows are already familiar with device drivers, which are small software programs that enable Windows to communicate with different hardware devices. Windows XP, Vista and Window 7 actually support quite a lot of hardware by default, but some hardware devices will need additional device drivers.
Missing Device Drivers
So what happens if these additional device drivers are missing? Well in most cases that will result in unknown device errors or unknown usb device errors. Windows will show a device not recognized error and list the unknown device in the “Other devices” category in the Device Manager. An unknown usb device error happens in case of a USB device, which is actually one of the most common unrecognized type of devices.
Below is an example of unknown devices in Windows XP.
Since Vista (and now also Windows 7) supports even more devices than Windows XP, you should expect unknown device errors to happen a lot less in Vista. But they do happen. Here is an example of the Device Manager in Vista with an unknown device.
Complicating the unknown device error is the fact that different device drivers are required for 32-bit and 64-bit versions of Windows. Drivers for 64-bit versions of Windows have been very hard to find in the past, but this has improved with the increased use of Vista and the recent release of Windows 7, which both come in 64-bit versions.
Unknown device errors can happen for all types of devices. As mentioned, the most common unknown device is a unknown USB device, and less common is the PCI unknown device. USB and PCI are both bus types that allow for hardware to communicate with the computer. Examples of unknown USB devices are USB webcams, mobile phones, and external USB hard drives. PCI unknown devices are more likely to be video cards, audio cards and network cards.
Solving an Unknown Device Problem
The most common cause for the unknown device error is a missing driver. The way to solve it is to find the right driver and (re)install the device driver for the hardware device. If you right-click the unknown device in the Device Manager you can select the driver update option. This will search for a device driver for your hardware.
For unknown USB devices, always try unplugging the device first and then re-plugging it after waiting a few seconds. Sometimes the device recognition fails without reason and simply re-plugging the USB device helps.
It is also useful to check the error code. You can find the error code by right-clicking the unknown device in the Device Manager, and selecting Properties in the popup menu. This will show you the device status, including the error code. Unknown devices often have error code 1, as this represents the status that the device is not configured correctly.
Other common error codes are:
- code 10, this device cannot start.
- code 28, the drivers for this device are not installed.
- code 31, the device is not working properly because because Windows cannot load the drivers required for this device.
- code 37, Windows cannot initialize the device driver for this hardware.
- code 39, Windows cannot load the device driver for this hardware. The driver may be corrupted or missing.
There are many more possible error codes, but not all result in an unknown device. Always try to uninstall the device and restart the computer as this will result in the driver being reinstalled.
If Windows does not have a driver for the unknown device, you will need to find and download a driver for the unknown device. In case you know the brand and model of the device, you can try to find the driver on the manufacturer’s website.
If you cannot find a driver for the unknown device or unknown USB device, you can try and use a driver finder program. This type of program will automatically detect and identify all your hardware devices, including unknown devices, and provide the latest drivers available for it. In a way, it acts as an ‘unknown device’ finder or locator.
Still could not find the driver for your unknown device? Leave a comment and I’ll see if I can help you out!
I have the problem my pc register a unknown device and my flash drive doesn’t work , and in my device manager there is a pci modem drivers that my drivers disc don’t have
What must I do to install my usb drivers and the PCI modem and the solve the usb device not reconized problem
I have a problem my pc register a unknown device and my flash drive don’t work it say usb device not recognized, and i can’t find any drivers for my PCi modem
what should i do to correct the problem
@marc – If you do not know the brand or model of your modem device, the easiest way is to use a driver finder program. The USB device can have multiple causes, did you try the tips in this article already?
i just installed windows 7 ultimate on my sony vaio vgn-sz160p/c
everything works well exepct of an unknown device with error code 28
and on the value has 2 choises
USB/VID_05CA&PID_1830&REV_0100
USB/VID_05CA&PID_1830
i will apreciated if u can help me
thanks in advance
@chris – I’ll have a look, I definitely know that the VID_05CA vendor is Ricoh, and HP uses a lot of those devices. They have the PID_1810 and PID_1870 in use in some laptops. Have not seen the PID_1830 yet.
Have your tried the original XP drivers in compatibility mode?
yes i did nothing works
thats the only problem with sony vaio on 32 bit windows7
i apreciate ur help i quess i have to live with that
by the way i think is my sd card reader doesnt reconized
thanks again for ur time and effort
i found the problem it was my cams drivers i folow ur advice and i downloaded
the windows xp drivers it works fine
the only problem i have now is that doesnt read my sd cards
by the way my sd cards are over 4mbs
sorry i ment over 4 gigs
@chris – Glad there is some improvement. Are you certain the reader supports those SD cards? Just try a smaller storage size one and see if that works first.
yes it works til 2gs
but i got a problem now with my hp pavilion dv6000
use to have vista home premium 32 bits and i instal windows7 ultimate and a got 2 unknown devices
the first one writes
PCI bus 5, devices 5, function 3 and the other
PCI bus 5, devices 5, function 2
they both have exclamation marks
i will apreciate ur help
Hi, can you please help me?
I have a USB flash drive and I have my 12page essay saved on it that is due in 4 hours, and it won’t open. I have Windows Vista. I have uninstalling and reinstalling all the USB port and I followed the devicemanager step as well
Thank You
Mary
I have an easynote R1938 with XP installed. It connects to the internet when hard wired but won’t connect to any wireless networks. The drivers for the wireless card are installed and updated and it shows as active but not connected in the sys tray. In the Device manager I have an unknown device showing but do not have any idea what the device may be. The ethernet connection and comms controller are installed and updated. Any idea what the unknown device may be and if it could be causing the lack of wireless connection?
cheers.
Should also include with item 12, I have tried installing vista and 7 but it crashes on start up saying it cannot use vista or 7 as the bios is not fully compliant and I cannot find any more updated or alternative bios update.
@BK – If your wireless device is working properly according to the device manager, then the unknown device should not normally affect the wireless connection.
There can be many reasons for wireless connections failing. Are you getting an error message when you try?
In any case, check the SSID, the security settings and make sure DHCP is used to get an IP number from the wireless router.
Regarding the unknown device, I would need to know the hardware id from the Details tab in the device properties (Device Manager), or you can try a driver finder application to see if it recognizes the device and offers any drivers for it.
this still does not work. i’ve tried it a million times. i have an xp and every time i plug in my iPod dock it says “unknown device,” then when the wizard searches for it, it never finds it. i need help with this ASAP!!!
I have a compaq presario and it installs XP, however, when I connect to the internet to download the updates the computer restarts itself automatically..as soon as I connect..do you know why..?
@Carol – Does the restart only happen when you use Microsoft Update or also if you browse the Internet to a different website?
No, it only happened when I connected to updates..as it scanned the PC for undates it needed that is when it would restart..now it won’t boot at all..the only thing it shows is the start up screen that says Compaq..I can’t even boot into the bios…
I have recently installed my w7601i phone drivers onto my vista home laptop and when i plug my phone into the usb it always gives me “unknown device”. when i try to update the driver it tells me that the right driver software is already installed on this computer. The error code is (Code 1)
@Carol – If you can’t get into the Bios or start Windows anymore, there must be a hardware problem. Best have a PC technician look at it.
@Jesse – Device error code 1 really means a driver problem. Either the wrong driver or a driver install error. Did you install the PCSuite from Sony Ericsson?
If possible, uninstall the driver software, reboot, clean the registry, and then try to reinstall the driver.
But really make sure you have the right driver, as a compatible driver might indicate that it works, while it does not really work.
Cannot find device driver PcI\VEN_8086&DEV_108E&SUBSYS_0000806REV_03\4&6C79FC5&0&04E0
Chip Active Managment Technology KCS
Computer MPC client pro 375 Socket 775 LGA Intel Pentium D 820
@Matt – I know that the device is indeed an Intel AMT device (PCI\VEN_8086&DEV_108E), but the specific SUBSYS details are unknown to me. Have you checked the compatible id’s in the device manager?
I just got an ipod touch from a friend. And it was able to sync once b4 with my itunes, but now my computer isn’t able to recognize its “driver”. I’ve tried to update the driver but it says that its already updated. Any knowledge about how to fix this would b greatly appreciated!