Unrecognized USB Device Problem

manytimes you have seen that, when plug a external device, we get error as:
"usb device not recognized".
The possible causes are:
1) Faulty Hardware or Firmware.
2) Not Supporting USB 2.0
3) Faulty system port or device port.
4) Damage cable.
5) Device is not properly connected.
6) Out-of-date firmware or basic input/output system (BIOS)
1) First try your device on some other system. There may be chance that it is problem with your system. Like problem in OS, system port.
2) Update the device driver. Download and install the latest driver from the Internet
3) Try the same cable on other system , to make sure it is not a cable problem.
4) Unplug and plug can also fix this problem. sometime, the cable is not properly attached.
5) Visit Microsoft Web site to see whether the Web site autodetects an updated driver for your device. Install all recommended drivers.
6) Update BIOS. Outdated BIOS can also be a cause. So, update your BIOS.
7) Start -->> Run -->> type devmgmt.msc -->>OK -->> Expand the Universal Serial Bus controllers node, and then follow these steps for each USB Root Hub that is listed:
  • Right-click the USB Root Hub, and then click Properties.
  • Click the Power Management tab.
  • Click to clear the Allow the computer to turn off this device to save power check box, and then click OK.