How to Delete an EFI partition in Windows 7

If you have an external 1TB USB hard drive that has been formatted on a Mac, the default partition type is EFI rather than the Windows standard of MBR. The Windows Disk Management tool will show the EFI partition on the disk but won’t allow you to delete it. Here’s how to delete it in Windows 7:

  1. With the USB drive connected, open a command prompt with elevated privileges.
  2. Start the disk partition utility by typing “diskpart“.
  3. Type “list disk” to see all of your connected disks (be positive you have the right disk!).
  4. To select a disk type “select disk #” where # is the disk number you want to delete the EFI partition from.  Type “select partition #” where # is the number of the partition you want to delete.
  5. Type “clean
  6. That’s it! The EFI partition is gone and you can now go back to Disk Manager and create a new partition and format the drive normally.