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Managing Windows Devices
The PCI Database web site

Hardware Compatibility List (Windows 8 only!)

Manufacturer support sites

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So far, every kind of computer system has a microprocessor device that can execute instructions, some kind of input device or devices to provide instructions and some kind of output device or devices to make the resulting output usable by humans.  Input and output devices, whether internal or external, include every type of keyboard, mouse, hard disk, monitor, printer, etc.  They all need little programs called drivers that are instructions for the processor to use when communicating with the particular hardware device.

When devices fail
Eventually, your printer, network interface card or some other device will stop working.  You may be lucky enough to get a message that leads you to a solution.  It could be a simple hardware problem, like a loose or worn data cable.  It could be a complex hardware problem, in which case you'll need to repair or replace the device.  Or it may very likely be a problem with a device driver that can be diagnosed and fixed with the Device Manager or a control panel.  Devices that require frequent handling, like printers, scanners, and cameras have only a control panel that lets you deal with settings issues as well as driver problems.  Other devices, like keyboards, mice and sound cards have entries in both the control panel and the Device Manager, but you should turn first to the control panel for these devices to resolve problems as you're likely to find more user-friendly options there.

The Device Manager
Although Apple Computer are the only licensed manufacturer of Macintosh computers, and easily control and update third-party device drivers, the situation is more complex on the Windows side where all the hardware is third-party.  All versions of Microsoft Windows since Windows 95 have included the Device Manager, which lets you view and control the hardware devices inside and some of those attached to ports on the outside of your computer.  It lists the devices, including even your processor, and tells you which need your attention, if any do.  The easiest way to open the Device Manager is to right click Computer or My Computer, then click Properties, then click the Hardware tab.  In the Hardware tab click [Device Manager].

In the list of devices, you see an icon for each device.  If there's a problem with the device or its driver, there may be an error indication like an icon superimposed over the device's icon.  Among the problems that can be diagnosed this way are:

Other Device, Unknown Device: This cryptic device 'name' in the list indicates attached hardware that is not recognized and can't communicate with Windows.  Could be that you've just completed a new setup of Windows, or you just upgraded Windows, or you've been trying to install a new device.  Could be your driver has simply become corrupted.  You can identify the unknown device manually, and then locate and install the required device driver.  Use the Device Manager and your internet browser, and follow this little procedure to identify the device and get the needed driver.  (You can also practice this procedure on any working device by following only through step 5 or so):

1. In the Device Manager list, right click the unknown device and then click Properties.

2. Click the Details tab in the Properties window.

3. In the drop down menu in Details, select “Device Instance ID” from the long list.  For Windows 7, it's called “Device Instance Path.”

4. You'll see a long string of characters, including “VEN” for the device vendor, and “DEV” for the device itself.  The four hexadecimal characters after VEN are the vendor code and the four after DEV are the device code.  Make a note of both codes.

5. Next, click the PCI Database link at the bottom of this article.  Use the “Search” fields in this web site to identify the vendor (manufacturer) and device names of this device.  Some of the results in the PCI Database web site provide links to the manufacturers' web sites.  But you can browse to it yourself: if the manufacturer is VMWARE, for instance, then their web site will be located at something like, but you can also use the database of manufacturer support sites link below.

6. Next, skip down in this article to step 2 of the ”Using a manufacturer's web site to update drivers” section and follow from that point to download and install your missing driver.

Disabled device: if you see a red X (95 through XP) or gray arrow pointing down (Vista through 8) in the Device Manager list, that device has been disabled either by the user or through some error.  Double click the device with the red X and click the General tab if it's not showing.  At the bottom of the General tab find a drop down menu labeled “Device usage” and check that “Do not use this device (disable)” is selected.  Click the drop down and select “Use this device (enable).”  Restart the computer and check the Device Manager again to make sure the device is enabled.

Hardware not working properly: if you see a black exclamation point on a yellow shield it means there's a problem with the device's driver.  It could be the wrong driver, or that the device is simply unplugged.

Hardware not recognized: if you see a yellow question mark in place of the device's driver, it means the hardware has not been properly installed.  The installation may be incomplete or the device may just be incompatible with the system.  Microsoft maintains Hardware Compatibility Lists for only its most recent versions of Windows.

With disabled, not working or not recognized devices, double click the device in the Device Manager list.  Check the General tab, under Device Status.  You will see a message with an error code to help determine what kind of issue Windows is having with the device.  Google the error code using a search string something like

device manager error code 43 windows xp

and look over the results for something like “How to fix error code 43...”

Duplicate devices and the Driver tab options
If the Device Manager lists two of any particular device, delete both of them.  To delete a device, double click the device and then click the Driver tab.  You'll find an [Uninstall] button near the bottom of the Driver tab-- click it.  If Windows asks if you want to restart, click [No] because Windows will likely use this opportunity to reinstall another copy of the one you just uninstalled.  Next, go back to the Device Manager window and repeat this procedure for the second duplicate.  Then restart the computer manually and Windows will correctly reinstall a single copy of the driver.  Open the Device Manager again and make sure there's only one copy of everything.

Drivers of even different devices sometimes conflict with each other.  If you notice this problem immediately after installing a new device, then chances are this one caused the problem, but this can happen when one of the drivers is simply out of date.  The [Disable] button on the Driver tab can be used to temporarily turn off a device.  Windows then acts like the device is not there.  This can be useful to determine which driver is causing the conflict.  If the yellow exclamation point icon and message show a resource conflict, disable first one of the two devices and test the one still enabled.  If it works, then the problem is with the second device.  Uninstall the offending driver and skip to the next section on Using a manufacturer's web site to update drivers and replace it. 

The [Update Driver...] button will do just that using Microsoft's collection of drivers, which may not be the most up to date or complete collection for your particular computer system.  You should instead update the driver using one downloaded from the web site of the manufacturer of the device or that of the manufacturer of the computer system itself.

Using a manufacturer's web site to update drivers
Nearly every device manufacturer has a web site with downloadable drivers.  Follow these general instructions:

1. You'll need the exact make and model of the device.  Dell and other computer manufacturers also keep the latest drivers for all of the devices in your computer.  In that case, you'll need the exact model number or 'service tag' of your complete system, which can be found on a label on the outside of the computer.  Either way, if the manufacturer is TrendNet, for instance, then their web site will be located at something like  You can also use the link below to the database of manufacturer web sites.

2. Use your browser to find the download area of the manufacturer's web site.  When you first get to the web site, look for a link for Support or Driver Downloads or some such related term.
Navigate to or search for the specific drivers you need.

3. Choose drivers here in the manufacturer's web site that were written for XP or Vista or whichever Windows your system has.  You must also choose either the 32-bit or 64-bit version depending on your system.  If, after correctly identifying your version of Windows, you can't find a driver here for your device, it means the device is no longer (or never was) compatible with that version of Windows, and you may need to get another device that is compatible.

4. Click the link to download the driver, and choose to Save the file to your desktop, (not to Run the file.)

5. Most drivers are free these days and include installers and all you have to do to install them is to double click the file you saved to your desktop.

Driver Rollback
Sometimes driver updates cause more problems than the driver you were trying to update.  Fear not.  Windows keeps track of the version history of your device drivers and can easily return your system to the older, more reliable driver that you replaced and updated.  Again, double click the device in the Device Manager's list, and then click the Driver tab.  Click the [Driver Rollback] button, and Windows will roll the driver back to the previous version.
February 10, 2013

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