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Turn off the PC, and put in the Windows installation DVD or USB key.
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Boot the PC to the DVD or USB key in UEFI mode. For more info, see Boot to UEFI Mode or Legacy BIOS mode.
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From inside Windows Setup, press Shift+F10 to open a command prompt window.
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Open the diskpart tool:
diskpart
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Identify the drive to reformat:
list disk
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Select the drive, and reformat it:
select disk <disk number> clean convert gpt exit
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Close the command prompt window.
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Continue the Windows Setup installation.
When choosing an installation type, select Custom. The drive will appear as a single area of unallocated space.
Select the unallocated space and click Next. Windows begins the installation.
Original source: https://docs.microsoft.com/en-us/windows-hardware/manufacture/desktop/windows-setup-installing-using-the-mbr-or-gpt-partition-style