Important Back up or transfer any files on your flash drive before starting this procedure. The contents of the flash drive will be deleted during the reformat process.
Plug the USB drive into a PC that's running Windows.
Open File Explorer.
Right-click Removable Disc (or USB Drive) in the left pane.
From the pop-up menu, select Format.
In the Format Removable Disc (or USB Drive) box, make sure File system is set to NTFS.