The “Unknown USB Device (Descriptor Request Failed)” error is a common USB-related issue in Windows 11 and Windows 10. It usually appears in Device Manager with a yellow warning icon under Universal Serial Bus controllers, indicating that Windows was unable to identify the connected USB device. When this happens, the affected device may not work at all, and Windows may display messages such as “USB Device Not Recognized” or fail to detect the hardware entirely.
This error occurs when Windows cannot read the USB device descriptor during the initial connection process. The problem may be caused by a faulty USB port, damaged cable, corrupted USB drivers, outdated chipset drivers, power management settings, BIOS issues, or even hardware failure of the USB device itself. Fortunately, in most cases, the issue can be resolved by reconnecting the device, reinstalling USB drivers, updating Windows, or changing power management settings.
This guide explains the best methods to fix the “Unknown USB Device (Descriptor Request Failed)” error in Windows 11 and Windows 10.
What Causes the “Unknown USB Device (Descriptor Request Failed)” Error?
When you connect a USB device, Windows requests its device descriptor to identify the hardware and load the appropriate driver. If Windows cannot read this information, it displays the Descriptor Request Failed error.
Common causes include:
- Faulty USB port
- Damaged USB cable
- Corrupted USB drivers
- Outdated chipset drivers
- USB power management issues
- Incompatible USB device
- Corrupted Windows system files
- Outdated BIOS or firmware
- Insufficient USB power
- Hardware failure of the USB device
Method 1: Reconnect the USB Device
A temporary communication problem between Windows and the USB device may prevent the descriptor from being read correctly.
Disconnecting and reconnecting the device forces Windows to detect it again.
Follow these steps:
- Disconnect the USB device.
- Wait about 10 seconds.
- Reconnect it securely.
- Try a different USB port.
- Test both USB 2.0 and USB 3.0 ports if available.
- Avoid using a USB hub during testing.
- Check whether the device is recognized.
If Windows identifies the device successfully, the issue was likely temporary.
Method 2: Restart Your Computer
A temporary USB controller issue can sometimes prevent Windows from communicating with connected hardware.
Restarting the computer reloads the USB controllers and associated drivers.
Follow these steps:
- Save your work.
- Click Start.
- Select Power.
- Choose Restart.
- Wait for Windows to load completely.
- Reconnect the USB device.
Check whether the error has disappeared.
Method 3: Reinstall the USB Drivers
Corrupted USB controller drivers are one of the most common causes of this error.
Removing the drivers allows Windows to install fresh copies automatically during the next startup.
Follow these steps:
- Right-click the Start button.
- Select Device Manager.
- Expand Universal Serial Bus controllers.
- Right-click Unknown USB Device (Descriptor Request Failed).
- Select Uninstall device.
- Confirm the removal.
- Repeat for any additional unknown USB devices.
- Restart the computer.
- Allow Windows to reinstall the USB drivers automatically.
Reconnect the USB device after Windows starts.
Method 4: Disable USB Selective Suspend
USB Selective Suspend saves power by turning off inactive USB ports. Occasionally, Windows may fail to restore communication with certain USB devices.
Disabling this feature often resolves USB recognition problems.
Follow these steps:
- Open Control Panel.
- Click Power Options.
- Select Change plan settings.
- Click Change advanced power settings.
- Expand USB settings.
- Expand USB selective suspend setting.
- Set it to Disabled.
- Click Apply.
- Click OK.
- Restart the computer.
Reconnect the USB device and test it again.
Method 5: Prevent Windows from Turning Off USB Controllers
Windows can automatically disable USB Root Hub devices to conserve power, which may interfere with certain USB devices.
Disabling this power-saving feature can improve USB stability.
Follow these steps:
- Open Device Manager.
- Expand Universal Serial Bus controllers.
- Double-click USB Root Hub.
- Open the Power Management tab.
- Clear Allow the computer to turn off this device to save power.
- Click OK.
- Repeat for each USB Root Hub.
- Restart the computer.
Check whether the USB device is detected properly.
Method 6: Update Chipset and USB Drivers
Chipset drivers control communication between Windows and the motherboard hardware, including USB controllers.
Installing the latest chipset drivers often fixes USB compatibility problems.
Follow these steps:
- Visit your computer or motherboard manufacturer’s support website.
- Search for your exact model.
- Download the latest chipset drivers.
- Download USB controller drivers if available.
- Run the installers.
- Restart the computer.
- Reconnect the USB device.
Verify that Windows now recognizes the hardware.
Method 7: Test the USB Device on Another Computer
Testing the device on another computer helps determine whether the issue is caused by Windows or by the USB hardware itself.
If the device fails on multiple computers, it is likely defective.
Follow these steps:
- Disconnect the USB device.
- Connect it to another computer.
- Wait for Windows to detect it.
- Test all functions.
- If necessary, replace the USB cable.
- Return to the original computer if the device works elsewhere.
This helps identify whether the hardware is faulty.
Method 8: Repair Windows System Files
Corrupted Windows files may interfere with USB device detection and driver installation.
Running the System File Checker and DISM tools repairs damaged operating system files.
Follow these steps:
- Open Command Prompt as Administrator.
- Run:
sfc /scannow- Wait for the scan to complete.
- Then run:
DISM /Online /Cleanup-Image /RestoreHealth- Restart the computer.
- Connect the USB device again.
If corrupted system files caused the problem, Windows should now recognize the device.
Method 9: Update BIOS and Windows
Older BIOS firmware and outdated Windows versions may contain USB compatibility bugs that prevent certain devices from working correctly.
Keeping both Windows and your system firmware up to date can resolve these issues.
Follow these steps:
- Open Settings.
- Click Windows Update.
- Select Check for updates.
- Install all available updates.
- Restart the computer.
- Visit your computer manufacturer’s support website.
- Check for BIOS or firmware updates.
- Install updates according to the manufacturer’s instructions.
- Restart the computer again.
Reconnect the USB device and verify that it is detected properly.
Conclusion
The “Unknown USB Device (Descriptor Request Failed)” error usually occurs when Windows cannot read the identification information sent by a USB device during connection. In many cases, the issue is caused by a faulty USB port, damaged cable, corrupted USB drivers, outdated chipset software, or power management settings rather than a hardware failure. Begin by reconnecting the device, trying a different USB port, and restarting your computer. If the problem persists, reinstall the USB drivers, disable USB Selective Suspend, prevent Windows from powering down USB Root Hubs, and update your chipset drivers. Repairing Windows system files and installing the latest Windows and BIOS updates can also resolve compatibility issues. If the device still isn’t recognized on multiple computers, the USB hardware itself is likely defective and may need to be replaced.
Frequently Asked Questions
1. What does “Descriptor Request Failed” mean?
It means Windows could not read the USB device descriptor, which contains the information needed to identify and initialize the device.
2. Can a faulty USB cable cause this error?
Yes. A damaged or poor-quality USB cable can interrupt data communication and prevent Windows from reading the device descriptor.
3. Will reinstalling USB drivers delete my files?
No. Reinstalling USB controller drivers only refreshes the driver software and does not affect data stored on USB devices.
4. How can I tell if the USB device is defective?
Connect the device to another computer. If it still displays the same error or isn’t detected, the USB device or its cable is likely faulty.
