Flash drives are a very convenient storage medium for documents. You get a lot of memory without it taking up much space. Thumb drives are also a nice way to backup documents. However, they are not foolproof and can have drive corruption from time to time. While flash drives do not often need formatting there are some signs that a format or disk check is in order. A typical sign that there is some problem with your thumb drive is when your files on the drive do not open or are otherwise inaccessible but there was no problem with the transfer of the file to the thumb drive.
Before doing anything, backup the data on the drive. Copy what you can to a good location on your computer. Then run your computer’s check disk utility. This procedure can fix minor issues on the device. While a check disk can delete files in bad sectors, it will leave good data intact. If a check disk does not fix the issue then a format is most likely in order.
The best route for a format of you flash drive is to call the vendor of your particular device and have the helpdesk walk you through the formatting process. Alternatively, there is software that came with your particular USB drive (or is available for download on their website) which will walk you through formatting the drive.
For those that want to do it themselves be forewarned that you try these procedures at your own risk. There is no guarantee it will work and it could render your thumb drive unusable.
On a Windows computer, plug in your thumb drive. Open up "My Computer". Right click on your thumb drive and select "format". Pick the appropriate file system for your drive (NTFS, FAT32, FAT, etc) and then hit the "start" button.
For the Mac OS, launch the "Disk Utility". Click on your flash drive and click the "erase" button. Select the appropriate file system and proceed with your erase.
Again, the above procedures should be done at your own risk. Ideally you should call the manufacturer and have them walk you through this procedure.