Unable to mount attached USB drive

Explanation:

Lightning server can not identify the USB drive that attached to the device for unknown reason. 

Solutions:

• Unplug the USB driver and replug again.
• If you are using bus powered USB drive (without external power supply unit), please make sure it does not drain more than 500mA/5V power from host computer or it wont work with Lightning device.
• Change to another USB drive and try again.