Hey there sony,
Sometimes, the reason why you are no able to access the USB drive is that it is faling. Still, you could try to access it and see if it will work. Let's try something, shall we?
Follow these steps:
1. Open command prompt
2. Type the following:
attrib -s -h -r X:/*.* / s / d
Then hit "Enter" and wait about for some seconds
Be careful! Respect the spaces between words and script. Change the letter X with that has been assigned to the USB device on your PC (that you can see it in My Computer. It can be anything, depends on each computer.)
3. Finally, browse the flash drive and delete the recycle folder and if there is another one called "Autorun" you have to delete that too.
Let me know if that worked.