USB not detected

the only option you have now is to take it to the service center as they will be able to recover your data for sure. Since the USB is not detected you cannot do anything . If there would have been a virus problem , the hardware would be detected but it wouldn't have worked. But since your USB is not even getting detected there is some problem with the USB !

i think your usb drive is broken... next time if the data is important, make sure you create at least two backups in case something like this happen again. You can try taking it to service center but i doubt that they can get any data from it.

I just had a laptop serviced under warranty at Best Buy, we took it to them originally and they said it was a software issue, its a common response with Best Buy, because I feel that their 'geek squad' isn't competent enough to know when there is a hardware problem, or when there is a software problem They told us we had to do a complete reinstall of Windows, which we had been trying to do but as soon as it got to the driver install it would stop, so we had to order recovery discs from Toshiba. A week later we were back at the store and it was a problem the mother board was shot. And when we got it back the mouse was suddenly busted they had to take it back even though it was off warrenty becaue we noted the problem when were there and they thought it would be fixed if we reinstalled windows fresh. So while it could be a software problem, my gut feeling tells me that you have a hardware issue with your computer.