Windows Setup: Installing using the MBR or GPT partition style
Updated: October 20, 2013
Applies To: Windows 8.1
When installing Windows on UEFI-based PCs using Windows Setup, your hard drive partition style must be set up to support either UEFI mode or legacy BIOS-compatibility mode.
For example, if you receive the error message: “Windows cannot be installed to this disk. The selected disk is not of the GPT partition style”, it’s because your PC is booted in UEFI mode, but your hard drive is not configured for UEFI mode. You’ve got a few options:
Reboot the PC in legacy BIOS-compatibility mode. This option lets you keep the existing partition style. For more info, see Boot a PC in UEFI Mode or Legacy BIOS-compatibility mode.
Reformat the drive for UEFI by using the GPT partition style. This option lets you use the PC’s UEFI firmware features.
From inside Windows Setup, press Shift+F10 to open a command prompt window.
Reformat your drive:
UEFI mode: Use DiskPart to clean the drive and convert it to the GPT partition style:
diskpart list disk select disk <disk number> clean convert gpt exit
Legacy BIOS-compatibility mode: Use DiskPart to clean the drive and use the default partition style (MBR):
diskpart list disk select disk <disk number> clean exit
At this point, you can close the command prompt window and then continue the Windows Setup installation.
Consider running Windows Setup through Windows PE, and use a script to detect which mode you’re in before installing Windows. For more info, see Boot Windows PE in UEFI or legacy BIOS mode.