Your USB-C hub may still light up. Power Delivery may continue charging the laptop, and HDMI may even display normally.

But in Device Manager, Windows shows:

Unknown USB Device (Device Descriptor Request Failed)

The device may also display:

Windows has stopped this device because it has reported problems. (Code 43)

This error is different from a normal missing driver.

Windows has detected electrical activity on the USB connection, but it could not complete the early identification process required to recognize the device properly.

Microsoft describes Code 43 as a condition where a driver controlling the device reports that the hardware failed in some way. Its general Device Manager guidance recommends reinstalling the device and scanning for hardware changes when the error persists.

The best way to fix it is to find where the USB recognition process stops.

Quick Answer

If Windows shows Device Descriptor Request Failed through a USB-C hub:

1. Disconnect the hub and every attached device.
2. Fully shut down the laptop instead of using Restart.
3. Disconnect power for 30–60 seconds.
4. Start Windows with nothing connected.
5. Connect the hub directly without an extension cable.
6. Add one simple USB device, such as a wired mouse.
7. Test the same device directly on the laptop.
8. Uninstall the Unknown USB Device in Device Manager.
9. Scan for hardware changes or restart Windows.
10. Update Windows, chipset, USB controller, Thunderbolt or USB4 drivers.
11. Test another laptop port and another computer.
12. Replace the cable, hub, or failing device only after isolating the source.

Do not install random third-party “USB repair” or driver-update software. Use Windows Update and the laptop manufacturer’s official support page.

The USB Enumeration Checkpoints

When a USB device is connected, Windows must complete several checkpoints before the device can work normally.

Power reaches the port
        ↓
The USB port resets the connection
        ↓
Windows requests the device descriptor
        ↓
The device reports its identity and capabilities
        ↓
Windows assigns the device an address
        ↓
The correct driver is loaded
        ↓
The device appears normally

A Device Descriptor Request Failed message usually means Windows could not receive or validate the basic identity information needed to continue enumeration. Microsoft’s technical Q&A explanation notes that failures can occur during the port reset, address assignment, device-descriptor request, or configuration-descriptor stage.

This explains why the hub can still receive power while USB data remains unavailable.

Checkpoint 1: Power Is Present, but Is Data Working?

A glowing LED does not prove that Windows has established a working USB data connection.

USB-C can carry several functions independently:

• Charging
• USB data
• HDMI or DisplayPort video
• Ethernet
• Audio

A hub may charge the laptop while its USB data controller fails to enumerate.

Use this symptom table:

If HDMI works but all USB data ports fail, see USB-C hub works with HDMI but USB ports don’t for a broader explanation of how video and USB data can fail independently.

Checkpoint 2: Identify Whether the Hub or One Accessory Is Failing

Disconnect everything from the hub:

• Keyboard
• Mouse
• USB receiver
• Flash drive
• SSD
• Webcam
• Printer
• Audio interface
• Phone
• Ethernet cable
• HDMI cable

Leave only:

Laptop → USB-C Hub

Open:

Device Manager → Universal Serial Bus controllers

Check whether the Unknown USB Device appears with the empty Hub.

The Error Appears with an Empty Hub

The likely suspects are:

• Hub host cable
• Laptop USB-C port
• Hub controller
• USB-C extension cable
• Adapter chain
• Laptop USB controller
• Power or firmware issue

The Empty Hub Appears Normally

Add devices one at a time.

Start with:

1. Wired mouse
2. Basic keyboard
3. USB flash drive
4. Webcam
5. External storage
6. Printer or audio interface

If the error appears only after one device is added, test that device and its cable directly.

Checkpoint 3: Perform a Real Power Reset

A normal Windows Restart does not always fully reset every USB controller and connected device.

Use this sequence:

1. Disconnect the USB-C hub.
2. Remove every device from the hub.
3. Shut down Windows completely.
4. Disconnect the charger.
5. Wait 30–60 seconds.
6. Hold the laptop’s power button for about 10 seconds if the manufacturer permits it.
7. Reconnect the charger.
8. Start Windows.
9. Wait until the desktop is fully loaded.
10. Connect the empty hub directly.
11. Add one USB device.

This clears temporary controller states and forces Windows to begin a new enumeration attempt.

If the error started after sleep or hibernation rather than during a normal connection, also review USB-C hub not working after sleep or restart.

Checkpoint 4: Bypass the Hub

A direct test separates the accessory from the hub.

Use:

USB device → Laptop directly

If the laptop has only USB-C ports and the problem device uses USB-A, a USB-C to USB 3.0 adapter for direct device testing allows you to bypass the multiport Hub and test one device at a time.

The Lention CB-C3s-3 supports USB 3.0 data transfer up to 5Gbps, is plug-and-play, and its product page currently displays Add to cart. Its role here is diagnostic: it helps determine whether the accessory works through a simple one-to-one connection. It cannot repair a damaged USB device, controller, or Windows installation.

Interpret the Direct Test

Remove all USB-C extension cables during this test. Connect the hub or adapter directly to the computer.

Checkpoint 5: Remove and Re-enumerate the Failed Device

Open:

Device Manager → Universal Serial Bus controllers

Look for:

• Unknown USB Device
• Device Descriptor Request Failed
• A yellow warning icon
• Code 43 under Device status

Then:

1. Right-click Unknown USB Device.
2. Choose Uninstall device.
3. Confirm the removal.
4. Disconnect the hub or accessory.
5. Restart Windows.
6. Reconnect the device after Windows loads.

Alternatively:

1. Uninstall the failed device.
2. Select the computer name at the top of Device Manager.
3. Choose Action → Scan for hardware changes.

Microsoft’s Device Manager guidance for Code 43 recommends uninstalling the failed device and scanning for hardware changes to reinstall it.

Do not uninstall every USB controller at once unless you understand how that may temporarily disable your keyboard, mouse, and other input devices.

Checkpoint 6: Update the Correct Drivers

The failed device may appear too early in enumeration for its normal manufacturer driver to load. However, the laptop’s USB controller, chipset, firmware, or Thunderbolt software can still affect the connection.

Update in this order:

1. Windows Update
2. Optional driver updates
3. Laptop chipset driver
4. USB controller driver
5. Thunderbolt or USB4 driver
6. Laptop BIOS or UEFI
7. Device-specific firmware, where available

Use the laptop manufacturer’s support page for:

• Dell
• HP
• Lenovo
• ASUS
• Acer
• Microsoft Surface
• Other Windows laptop brands

Microsoft also recommends updating, rolling back, or reinstalling the relevant driver when Code 43 begins after a driver or Windows change. See Microsoft’s official Code 43 troubleshooting guidance for the documented driver workflow.

Although that page is written around graphics devices, its update, rollback, uninstall, and rescan process reflects the standard Device Manager approach to Code 43.

Checkpoint 7: Check Power and Peripheral Load

Enumeration may fail when a device resets because the connection cannot provide stable power.

This is more likely with:

• External hard drives
• SSD enclosures
• Printers
• USB audio interfaces
• Capture cards
• Webcams
• Phones charging through the Hub
• Several devices starting simultaneously

Test:

1. Remove every high-power device.
2. Connect the laptop charger.
3. Connect power to the Hub’s PD input if supported.
4. Add one low-power device.
5. Add high-power devices individually.

Do not connect a USB device to a port labeled only:

• PD
• Power Delivery
• Charging
• 60W
• 100W

These ports are commonly charger inputs rather than USB data ports.

Checkpoint 8: Look for a Physical Connection Problem

Inspect:

• USB-C plug
• Laptop USB-C port
• Hub host cable
• USB-A ports
• Device cable
• Bent contacts
• Dust or debris
• Loose connectors
• Cable movement

Stop using the connection if:

• Moving the cable causes Windows connect/disconnect sounds.
• The device appears only when the plug is held at an angle.
• The Hub becomes unusually hot.
• The error repeatedly appears and disappears.
• The same port fails with several devices.

A descriptor request cannot complete reliably if the connection resets during the initial USB handshake.

What Not to Do First

Avoid these actions at the beginning:

• Editing the Windows Registry
• Disabling every USB power-saving setting
• Installing unknown driver packages
• Formatting a USB drive
• Resetting Windows
• Replacing the Hub before testing devices directly
• Connecting the Hub through several adapters
• Updating BIOS from an unofficial source

Start with isolation, a full power reset, Device Manager re-enumeration, and official updates.

When the Error Points to Hardware Failure

Hardware becomes more likely when:

• The same device shows Code 43 on several computers.
• The Hub shows the error while completely empty.
• Several known-good devices fail through one Hub port.
• The host cable is permanently attached and unstable.
• The device reports USB\UNKNOWN repeatedly.
• Reinstalling drivers and scanning hardware changes makes no difference.
• The error started after a drop, cable pull, liquid exposure, or electrical event.

Microsoft defines Code 43 as a reported device failure and advises checking hardware documentation or contacting the manufacturer after the standard troubleshooting steps have been completed.

Fast Diagnosis Matrix

FAQ

What does “Device Descriptor Request Failed” mean?

Windows detected a USB connection but could not obtain the basic identification information required to enumerate and configure the device.

Is Code 43 always a driver problem?

No. It can involve hardware, cable, port, power, firmware, the USB controller, or a driver. Test the device directly and on another computer before assuming the Windows driver is the only cause.

Why does the Hub still charge my laptop?

Charging and USB data use different parts of the USB-C connection. Power can continue even when USB data enumeration fails.

Why does HDMI work while USB devices show Code 43?

Video and USB data are separate functions. A working HDMI connection does not prove that the Hub’s USB data controller has initialized correctly.

Should I uninstall the Unknown USB Device?

Yes. Uninstalling it and scanning for hardware changes can force Windows to attempt a fresh enumeration. Disconnect important storage devices before making changes.

Should I uninstall every USB Root Hub?

Not as the first step. Doing so can temporarily disable input devices. Begin with the specific Unknown USB Device.

Can a USB-C to USB-A adapter help?

It can help with diagnosis by connecting one USB-A device directly to a USB-C laptop port and bypassing the multiport Hub. It will not repair faulty hardware.

When should I replace the Hub?

Consider replacement when the empty Hub shows Code 43 on multiple computers, its cable is unstable, or several known-good devices fail through it after official driver and firmware checks.

Final Thoughts

When Windows shows Unknown USB Device (Device Descriptor Request Failed), trace the recognition process in order:

Power → Port Reset → Device Descriptor → USB Address → Driver

Then isolate the setup:

Empty Hub → One Device → Direct Connection → Another Port → Another Computer

If the accessory works directly but not through the Hub, focus on the Hub, power, host cable, and port.

If the accessory fails everywhere, focus on the device and its cable.

Do not replace hardware based only on the yellow warning icon. A controlled direct test and a fresh Windows enumeration usually reveal which part of the connection is actually failing.