USB 2.0 Unknown Device Issues in XP

Windows XP includes native USB support. Windows Update added support for USB 2.0 devices in January 2002. If XP does not recognize a USB 2.0 device, the cause may lie with the system's drivers, issues related to the registry or the hibernation function. Before checking the functionality of a USB device, ensure the port is USB 2.0 compatible and your system has 2.0 support installed via the Device Manager.

Hibernation Timeout

Immediately connecting a USB device when resuming operation from standby or hibernation may result in your computer failing to recognize the device and listing it as "Unknown." This is caused by XP not initiating USB functionality when the system comes out of sleep mode. To fix this problem, disconnect the USB device and reconnect it after several seconds so it may be properly identified. Avoid this error by waiting a moment after the system resumes to connect any USB devices.

Registry Errors

The registry contains entries informing the system how to recognize and connect USB devices. If these entries become corrupt, change or are otherwise rendered unusable, USB 2.0 devices may display as unknown devices when connected. Microsoft's Fixit services can automatically repair the damaged portions of the registry. You can also use a third-party registry repair program such as Uniblue Registry Booster or Advanced Registry Optimizer.

Missing Drivers

If the device requires a specific driver for correct operation, the system may show USB 2.0 devices as unknown if the driver is not installed. If the device came with an installation CD, use it to reinstall the driver or visit the manufacturer's website. See instructions included with specific USB 2.0 devices for information on driver installation procedures.

Malfunctioning Drivers

 

Missing, malfunctioning, outdated or virus-corrupted drivers may also cause connected USB 2.0 devices to register as unknown, even if the system is properly configured. To fix nonfunctional drivers, remove them. Type "Device Manager" into the Start menu search field and press "Enter." Double click on the USB device and navigate to the "Driver" tab. Click "Uninstall" to remove the driver. Reinstall the driver from the device's CD or the manufacturer's website. Use caution, however: never uninstall a driver until you have a way to reinstall a working copy.