My USB flash drive is not recognizing in any system?

Before it was works great.When I plug my Flash drive, it is not recognized by the system. Even drive letter is not shown. How can I make it working.My USB flash drive is not recognizing in any system?
Try changing the drive letter, like this:





Have the drive plugged in





Right click ';my computer'; on the desktop





Select manage





Go to ';Storage'; and ';Disk management'; underneath it (it's a branch of it)





Your drive should show up here





Right click on the drive that is the USB port with the drive in it (it might be called just ';mass storage device';)





Select ';Change drive letter and paths';





A menu will pop up. Select change';





Pick a new letter for this drive, one that is NOT YET used for any other drive, like Q or something.





Reboot your computerMy USB flash drive is not recognizing in any system?
Please follow the instructions in the following article and see if it helps:





http://www.technize.com/2007/06/30/how-i-got-my-corrupt-usb-drive-working-again/
you could maybe, if you are willing to, somehow wipe everything off of the flash drive or buy a new one. im suggesting the new one but if you have important files on your current one, you should get somebody to look at it.
Its might have been affected with a worm or a virus
Get a new one. They're really cheap.
Buy a new one