Please see below for instuctions to correct USB I use, which should correct your USB drive. Please change NTFS to your preferred file system, usually FAT or FAT32
Many thanks and hope it helps
1.Bring up the command prompt. Easiest way is to go to the Start menu and type in “cmd” in the search box and hit enter.
2.In the command prompt window, type “diskpart”. That will launch another window with a DISKPART> prompt.
3.Type “list disk” to find out which disk your USB drive is. It should be pretty obvious from the size of the disk. If it’s not, alternatively, you can search “Computer Management” under the Start menu, and then click on “Disk Management”. You should see something that says “Disk 1 Removeable” or something similar.
4.Once you know which disk you want, in the Diskpart window, type “select disk 1″ (or whatever number your thumb drive happens to be assigned to). Diskpart should tell you that this is now the selected disk,
5.Type “clean”. This will get rid of all the old information on the disk, as well as any partitions. Diskpart will tell you when this has succeeded.
6.Type “create partition primary”. This sets up the new partition (one big one instead of a small one) for the drive.
7.Type “select partition 1″ to select the partition you just created.
8.Type “active” to mark the selected partition as active.
9.Type “format fs=ntfs quick” to format the drive. This may take a few minutes depending on the size of the drive.
11.Type “exit” to leave the Diskpart program.
Now remove the thumb drive from the USB port, and then plug it back in. It should come up at its original size. Ta-da!
Just as a word of caution, Diskpart doesn’t seem to have any confirmation prompts built into it. So BE CAREFUL which drive you’re telling it to use, or you might end up formatting something that shouldn’t be formatted.