Sometimes, we find that a pen drive simply cannot be formatted using the Disk Utility or gparted in Linux. In such a situation, open a terminal on your Linux computer, and enter the command as below to format the pen drive.
$ sudo mkfs.vfat -n ‘Label’ -I /dev/sda <enter>
where ‘Label’ in the quotes can be any name you want to give to the label of the pen drive.
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