Why doesn't the PC recognize USB device?
It is possible to check if the USB controller is working properly using the Device Manager. Please refer to the procedure below:
1) Go to [Start]->[Settings]->[Control Panel].
2) Double-click on the "System" icon to open [System Properties].
3) Click the [Device Manager] tab and choose [View Devices By Type].
4) Click to highlight [Universal Serial Bus Controller] and make sure there is no [!] or [X] mark on it.
* Re-install the driver which has [!] or [X] mark.
* Re-install USB device driver when USB controller works properly but doesn't recognize USB device.