UEFI: how to force windows to use only 1 partition?

Question

on my old computer that used the good old BIOS, this is how i setup my partitions using gparted on a linux livecd:

create partition table format MBR (msdos)
create primary NTFS partition
created extended partition with a EXT4 partition inside it
install grub on the MBR and have dual boot and lifes good

now i got a UEFI laptop and it seems that i cant do that anymore, this is what i tried (again using gparted from a linux livecd):

create partition table format GPT (instead of msdos MBR)
create primary NTFS partition
create primary EXT4 parition (now all partitions are primary)

but when i try to install windows by selecting the NTFS partition i get an "We couldn't create a new partition or locate an existing one. For more information, see the Setup log files" error.

if i remove all partitions and let windows create the partitions itself on an empty HDD it works, but it creates a lot (3 or 4) small partitions, called recovery and system files and whatnot.

when i used MBR one single partition worked fine, why doesnt it work now and how can i change that?

thanks.

score 2 · Answer 1 · edited Mar 20 '17 at 10:16

You cannot. You're not in the world of MBR partitioning any more, where (some) boot managers live in the "computer virus area" of your disc and you have to worry about a limit of four primary partitions.

In all your years of dual booting, your firmware was bootstrapping your operating systems in a completely different way to how it does now. Now, your system has a system-wide EFI system partition. It does not contain "EFI drivers" as Ramhound erroneously states. But it does contain the Microsoft Boot Manager and BCD store, and the operating system loader programs for other operating systems on your machine.

Other partitions will be

your (two) boot partitions, where Windows NT and Linux are installed,
your partition for GRUB (if you really think that you still need it),
and potentially:
- a partition containing the Windows Recovery Environment,
- a Microsoft Reserved partition so that you can convert the basic disc to a dynamic disc should you want to,
- any OEM utility partitions, and
- a /home partition for Linux perhaps.

But this is perfectly fine. This number of partitions comes nowhere near the (default) limit of the EFI partitioning scheme. Many of the utility, reserved, and system partitions need only around a eighth of a GiB, compared to your boot and home partitions which will be in the tens if not hundreds or thousands of GiB. So space is only a major concern to people without a sense of perspective. The only real problem here is that you entirely filled up your disc by hand before installation, instead of simply leaving a relatively (compared to your data/boot partitions) small amount of unpartitioned space for the setup program to claim for these partitions.

UEFI: how to force windows to use only 1 partition?

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