How To Fix: Unknown USB Device (Device Descriptor Request Failed)

If your external USB device is not recognized by Windows 10, and meet Unknown USB Device (Device Descriptor Request Failed) error in Device Manager, use solutions here to troubleshoot and fix the error. 
As you have noticed, the USB Device in Device Manager has a yellow triangle on it:

The error can be caused by hardware issues. So first, follow below simple instructions to do the troubleshooting.
1.  Try the device on a different USB port. This will figure out if problem is caused by a broken port. 
2. Connect the device to another PC. This will figure out if the external device has problem.
3. Plug out the USB device, restart the computer and plug in back the USB device.
If there is no problem with the USB port and the device, read on and try the following methods. You can start at the top of the list and work your way down.
Method 1: Troubleshoot the Error
In the first method, we will try to fix the issue using Windows Troubleshoot. Windows Troubleshoot is Windows’ inbuilt tool that searches for issues and fixes them. Many users have fixed the error using this method. Follow the steps to fix the problem.
1. Open Troubleshoot. To open Troubleshoot, Go to Cortana and type Troubleshoot. Select Troubleshoot from results.

2. The last step will open a Troubleshoot window. Here, click on Hardware and Devices.

3. Now the Windows will check for issues. When the process is done, click on Apply this Fix or Apply Repair Automatically, whichever appears.
4. After applying the fix, you just need to restart your computer.
This should fix the problem. If you are still facing the problem, follow the next method.
Method 2: Reinstall Unknown USB Device Driver
1. Open Device Manager. Right-click on the Start menu button and select Device Manager.

2. Now, look for Unknown USB Device (Device Descriptor Failure). It is located under Universal Serial Bus Controllers. Expand it and right-click on Unknown USB Device (Device Descriptor Failure). Click on Uninstall device.

3. Now, unplug the USB device from your computer, if it wasn’t already unplugged, and plug it back in the USB slot.
4. Scan for hardware changes. On the Device Manager window, click on Scan for hardware changes.

Windows will now reinstall the Unknown USB Device (Device Descriptor Failure) drivers. This should fix the issue. If the problem is still not solved, try the next method.
Method 3: Update USB Device’s Drivers
1. Right-click on the Start menu button and select Device Manager.

2. Now, look for Unknown USB Device (Device Descriptor Failure). It is located under Universal Serial Bus Controllers. Expand it and right-click on Unknown USB Device (Device Descriptor Failure). Click on Update Driver.

3. Click on Search automatically for updated driver software.

Now the Windows will download and install the latest drivers for the troubled USB device. When the process is complete, restart your computer and you will be free of the error.
If this method didn’t work for you and you are still stuck with the error, try the next method.
Method 4: Turn Off Fast Startup
1. Open the Control panel. To do this, go to Cortana and type Control panel. Click on Control Panel from results.

2. The last step will open Control Panel. In the Control Panel window, click on Choose what the power button does. It is located on the left side of the window.

3. Now, select Change settings that are currently unavailable.

4. Here, you need to unmark the box beside Turn off fast startup (recommended). It is located under Shutdown settings. After that, click on Save changes.

5. Now restart your computer.
After restarting the computer, check if the problem is solved. If the issue still persists, try the next method.
Method 5: Disable USB Selective Suspend Settings
1. Open Power Options. Right-click on Start menu button and select Power Options.

2. The last step will open the Power Options settings window. Here, look for Additional power settings and click on it. It will be located under Related settings.

3. Now, click on Change plan settings of the selected plan on your computer.

4. In the Edit Plan Settings window, select Change advanced power settings.

5. The last step will open a small Power Options window. Here, look for USB Settings and expand it.

6. Now, expand USB selective suspend setting. You need to change the status of all the entries to Disabled. After that, click on Apply and then on OK.

Method 6: Uninstall USB Root Hub Drivers
1. Right-click on the Start menu button and select Device Manager.

2. Expand Universal Bus Controllers. Here, right-click on the first USB Root Hub select Uninstall device.

3. Repeat the above step for remaining USB Root Hub devices.
4. Restart your computer.
After performing the restart, the Windows will recognize USB Root Hubs as the new devices and will install its drivers automatically. This should fix the problem. Connect your USB device in the USB slot, it will work properly now.