Unknown Device next to a yellow exclamation mark
Now if you see such an entry, it may be difficult to determine the cause of this unknown device, because there are few indications of what generates it. The main reason for the Unknown Device to display in your Device Manager is because you have a device that is not working correctly. To fix this issue, obtain an updated driver for the device via Windows Update or by a direct download from the internet.
Causes of unknown devices in Device Manager:
The device does not have a device driverUnrecognized Device IDUsing an older Microsoft Windows Device DriverFaulty Hardware or Firmware
For a detailed read on manual troubleshooting visit KB314464. Read: How to find, download and install Drivers for Unknown Devices or Hardware.
Unknown Device Identifier
You can check out Unknown Device Tool. It is a small utility available at Sourceforge that was written to provide computer technicians with a simple way to identify those “Unknown Device” devices that show up in Microsoft Windows after a fresh install.
Run the portable app and all the Hardware Devices that are listed as Unknown Devices will be listed. However, this app only displays PCI and AGP devices. It will not be able to help with ISA-based devices and original PCMCIA cards. Moreover, it shows all devices found in the Windows registry including devices that no longer exist. There is another freeware Unknown Device Identifier. This tool allows you to identify the Unknown Devices and gives you a detailed summary for the manufacturer name, OEM, device type, device model and even the exact name of the unknown devices. You can also use the Driver Verifier Manager to troubleshoot Driver Problems. Additional resources:
