Problem EFI partition

So I just bought a new PC that came without an SSD. I placed one in it and installed the OS on it. I have two other drives on the system as well. The 2TB HDD that came with the PC and a 1TB external HDD connected through USB. I'm trying to clear the 2TB completely to use for backing up the C: drive and the external disk but there's an EFI partition that I cannot get rid of. Even using diskpart "delete partition override" or "clean" both fail. It's just bugging me because it is sitting right between two unallocated sections,causing a split in the available space on the drive. An image of this in disk management is attached.

When you installed Windows 10 to the SSD, you still had the HDD connected as drive 0 and the UEFI firmware set to boot from it. Therefore, Windows used the EFI System partition on Drive 0 as the "system" partition that the computer boots from. What you should have done is connected the SSD to SATA port 1, left all other drives disconnected, install Windows 10, then connect the HDDs to SATA ports 2 and 3 and any DVD drives to port 4+.

Notice this in step 2 of our tutorial for installing Windows 10:
Windows 10 - Clean Install

2. Temporarily disconnect all non OS hard drives until Windows installation has finished. This is to avoid Windows Setup from installing files on other hard drives by mistake.

So I assume that I need to reinstall with the hdd disconnected? Wouldn't be a big deal if so since it's only been a few hours with the only thing I have done is update Windows.

Inexplix said:

So I assume that I need to reinstall with the hdd disconnected? Wouldn't be a big deal if so since it's only been a few hours with the only thing I have done is update Windows.

Yes, and physically connect the SSD to the lowest numbered SATA port.