[TIP] How to get Windows installed onto a GPT partition

I got a warning that I can’t install Windows to a GPT partition:

there is also another scenario where the installer gives a warning about not being able to install to MBR when using EFI bios:

Is there a bios setting which needs to be changed? I can’t delete my HGST 4Tb disk as it has data and I need it in GPT format because MBR only addresses up to 2Tb.

Edit final solution:

Apparently my bios/UEFI firmware has a limitation in that if a USB flash is formated with NTFS instead of FAT32 to contain the windows 7 installer then the required option to boot with UEFI:Flash_Drive_Name is not there. Therefore I made sure to keep my install.wim below 4Gb and used FAT32 option in Rufus 2.1.

Guides to prepare image:

[Guide] Integration of drivers into a Win7/8/10 image

(found windows updates downloader pretty self-explanatory apart from needed to double click the .ul update list to get the program to show the list.

Outdated: Edit found my answer:


"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 to UEFI Mode or Legacy BIOS mode.

Reformat the drive for UEFI by using the GPT partition style. This option lets you use the PC’s UEFI firmware features.

You can do this yourself by reformatting the drive using the instructions below, or if you need to preserve the data, use a third-party utility to convert the drive to GPT format.

Why should I convert my drive?

Many PCs now include the ability to use the UEFI version of BIOS, which can speed up boot and shutdown times and can provide additional security advantages. To boot your PC in UEFI mode, you’ll need to use a drive formatted using the GPT drive format.
Many PCs are ready to use UEFI, but include a compatibility support module (CSM) that is set up to use the legacy version of BIOS. This version of BIOS was developed in the 1970s and provides compatibility to a variety of older equipment and network configurations, and requires a drive that uses the MBR drive format.
However, the basic MBR drive format does not support drives over 4TB. It’s also difficult to set up more than four partitions. The GPT drive format lets you set up drives that are larger than 4 terabytes (TB), and lets you easily set up as many partitions as you need.
Reformatting the drive using a different partition style

To wipe and convert the drive by using Windows Setup

Turn off the PC, and put in the Windows installation DVD or USB key.
Boot the PC to the DVD or USB key in UEFI mode. For more info, see Boot to UEFI Mode or Legacy BIOS mode.
When choosing an installation type, select Custom.
On the Where do you want to install Windows? screen, select each of the partitions on the drive, and select Delete. The drive will show a single area of unallocated space.
Select the unallocated space and click Next. Windows detects that the PC was booted into UEFI mode, and reformats the drive using the GPT drive format, and begins the installation.
To manually wipe a drive and convert it to GPT:

Turn off the PC, and put in the Windows installation DVD or USB key.
Boot the PC to the DVD or USB key in UEFI mode. For more info, see Boot to UEFI Mode or Legacy BIOS mode.
From inside Windows Setup, press Shift+F10 to open a command prompt window.
Open the diskpart tool:
Identify the drive to reformat:
list disk
Select the drive, and reformat it:
select disk <disk number>
convert gpt
Close the command prompt window.
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.
Make sure Windows Setup boots to the correct firmware mode

To automate this process, you’ll need to run Windows Setup through Windows PE, and use a script to detect which mode you’re in before installing Windows. For more info, see WinPE: Boot in UEFI or legacy BIOS mode. "

Also this:


and this (finally I think I found a solution):

@ megatron:

Thanks for having started this thread and congratulation, that you were able to solve your problem yourself. It was a very good idea to add a guide about how to get Windows installed onto a GPT partition.
To make it easier for visitors to realize the content of the thread I have renamed the title. If you don’t like it, you can change everything by editing your start post.

Thanks again!
Dieter (alias Fernando)

I spoke too soon, I have found nothing but problems trying to do this. Currently I am falling back to DVD as it apparently has some code that the windows 7 USB does not. I want to make a dual boot, for testing purposes. My SSD already has MBT partitioning and a windows 7 install installed via USB key.

I tested with a DVD I already had and it got so far but I believe because it was made for my previous motherboard it didn’t have the right drivers to continue.

The only driver, which is absolutely needed, is the mass storage one (AHCI/RAID), which is needed to detect the current system drive and the target drive, where you want to install the second OS.

most of users will come across this problem when they install system. in order to solve the problem, users can use disk management or diskpart in windows to convert mbr to gpt on an empty disk. if there are data on hard disk, you should delete all of them before the conversion. to avoid deleting data, you can try third party software such as AOMEI Partition Assistant
more information:

@ verki:

Welcome at Win-RAID Forum and thanks for your contribution.

Dieter (alias Fernando)