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Unable to remove EFI partition from installer media

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Working on my first Hackintosh build using Clover, and made a mistake that required me to start the installation process over. No big deal, I think to myself, until the USB drive I'd just used for installation couldn't/wouldn't boot. I decided to wipe and re-partition the usb drive and try again, but found myself unable to delete/remove the EFI partition on the drive. I've tried many different techniques using Disk Utility, gdisk, fdisk & diskpart on windows all to no avail.

Disk Utility can't erase the EFI partition and reports "MediaKit reports not enough space on device for requested operation".

gdisk reports "Found valid GPT with protective MBR; using GPT."

I've followed all of these suggestions to a tee, and haven't had any luck:
http://www.mede8erforum.com/index.php/topic,14019.0.html
https://sixohthree.com/934/removing-all-partitions-in-mac-os-x
http://superuser.com/questions/508026/windows-detects-gpt-disk-as-mbr-in-efi-boot
https://discussions.apple.com/thread/4046267

So far, I've been able to "hide" the EFI partition by formatting the drive as MBR, but can't actually get it to go away. Hopeful that a solution to my problem is out there, I'm looking forward to giving life to my build!
 

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To allay your frustrations, how about using another usb drive they only cost peanuts these days - just my small suggestion so that you can get on with the installation and not make the same error again. Once that is out the way, you can return to the trouble some usb drive and try reformatting it again to be used for something else.
 

Going Bald

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So, in disk utility select the main USB, not the partition, in the left pane. Select format and in right pane change Current to 1 partition and name it, select OS X Extended (Journaled) and hit partition continue.
This creates a new EFI partition. Disk utility always creates this partition and it cannot be deleted. If you just want to erase the contents of the partition, use EFI Mounter app to mount the EFI, erase it and unmount it.
 
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I went through the process you detailed and ran into a familiar situation:

I mounted the EFI partition using EFI Mounter, and couldn't erase it (gave the same error I mentioned in my original post), deleting it using Disk Utility hides the partition, but doesn't get rid of it permanently.

Screen Shot 2015-06-23 at 9.34.35 PM.png
Here's the USB drive with both partitions
Screen Shot 2015-06-23 at 9.35.49 PM.png
Before formatting, I went into 'options' and used the GUID partition table. The new partition is being written to 'Disk1s2', the other partition is still there!
Screen Shot 2015-06-23 at 9.36.24 PM.png
Using Disk Utility in debug mode, you can see the hidden EFI partition. The main partition is also listed as 31.57, should be 31.91
 
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Why worry 'bout the EFI partiton, ignore it... If an EFI partition exist and it's empty then the bios will also ignore it. Guess maybe I'm missing something.
 
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