Y'all this procedure works like a charm
Scenario: When formatting a previously Mac formatted drive in Windows 7 you are unable to remove the EFI System partition/volume.
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Step 1: With the USB drive connected, open a command prompt with elevated privileges.
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Step 2: Start the disk partition utility by typing diskpart.
Step 3: Type list disk to see all of your connected disks (be sure you’re working on the right disk, if you select the wrong disk you’ll be sorry – see disclaimer). To select a disk type select disk # where # is the disk number you want to delete the EFI partition from.
Step 4: Type select partition # where # is the number of the partition you want to delete.
Step 5: Type delete partition override
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