Formatting a USB drive on PC - Plug the USB drive into a spare USB port and then open Explorer.  - On the USB drive icon 'right click' and select 'Format', a window will then open, click the drop down box labeled 'File System'. You will see a choice of NTFS, FAT, FAT 32 and exFAT. Select either FAT (the most commonly used) or FAT32.User-added image-Once the FAT/FAT32 format is selected choose if you want to do a Quick Format or if not un-tick that option. All you need to do now is press the 'Start' button and the format process will be begin. 

Formatting a USB drive on MAC

- Plug the USB drive into a spare USB port, open Finder then search for the Application 'Disk Utility' and launch it.

- Once the Disk Utility launches select your USB Disk in the left hand column, select the tab 'Erase'.User-added image- In the drop down box for the 'Format' select 'MS-DOS (FAT)'. Enter a name for your USB drive should you wish to. Then hit the 'Erase' button. User-added image- Finally a confirmation box will pop up. Hit the 'Erase' button to complete the process.User-added image