Unknown device

Question

How do I identify an unknown device on my

tablet

Answer 1

Open Device Manager.

Right click the Unknown device and select Properties.

On the resulting dialog, select the Details tab.

Set the Property drop-down menu to Hardware ID's

Right click and copy the top entry in the resulting list.

Then, please paste that entry into your next reply.

Answer 2

On a Windows tablet, an “Unknown device” usually means Windows can see the hardware but either:

• The USB/driver enumeration failed, or
• No matching driver/INF was found for the device.

Use these steps to identify it:

1. Open Device Manager
   • Press Windows key + X and select Device Manager.
   • Look under Other devices or any entry with a yellow warning icon and named Unknown device.
2. Check the Hardware IDs
   • Right‑click the unknown device > Properties.
   • Go to the Details tab.
   • From the Property drop‑down, select Hardware Ids.
   • If enumeration succeeded but no driver was found, you should see a value like USB\VID_045E&PID_F001.
     • VID_#### is the vendor ID.
     • PID_#### is the product ID.
   • If the device failed enumeration, it may show USB\VID_0000&PID_0000 and Hardware Id = USB\UNKNOWN, which indicates a low‑level USB problem.
3. Interpret what you see
   • Normal USB device with no driver (Code 28):
     • Device enumerated successfully but Windows has no driver. The Hardware Id (for example, USB\VID_045E&PID_F001) can be used to search the manufacturer’s site for a driver.
   • Failed USB enumeration (often Code 43, USB\UNKNOWN):
     • The USB stack could not complete basic requests like Set Address or Get Device Descriptor, or the descriptors were malformed. In this case, the issue is usually with the device firmware or hardware, not the tablet.
4. If it shows a valid VID/PID
   • Use the VID/PID pair (for example, VID_045E and PID_F001) to:
     • Identify the manufacturer and model via their support site.
     • Install the correct driver or app if the manufacturer provides one.
5. If it shows USB\UNKNOWN or VID_0000&PID_0000
   • Try a different USB port or cable (if external).
   • If it’s an internal component on the tablet, this usually indicates a hardware or firmware fault in that component. In that case, contact the tablet manufacturer’s support.
6. For advanced USB troubleshooting (optional)
   • Advanced users can capture a USB ETW trace and analyze it with Netmon to see where enumeration fails (for example, stalled GET_DESCRIPTOR requests). This is mainly useful when debugging device firmware.

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References:

• Case Study: Troubleshooting an unknown USB device by using ETW and Netmon
• How to connect to a USB device (UWP app)