Explanation Disk Management is a tool that allows users to create, format, delete, shrink, extend, and manage partitions on hard drives. If the external hard drive is not formatted or has an incompatible filesystem type, Disk Management can be used to format it with a supported filesystem type such as NTFS, FAT32, or exFAT. Device Manager, Disk Cleanup, and Disk Defragmenter are not tools that can format a hard drive.