GPT Disk Partition Layout for Windows 10 OS in a UEFI based PC

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There is a certain partition layout requirement in the UEFI-based computer which is required by the Windows 10 OS to work properly in the GPT Disk. If the disk already does not have a required partition layout then the Diskpart tool needs to be used to create a custom partition layout.


UEFI Firmware

The most modern computer has UEFI-based firmware which supports the following types of booting.

  1. Legacy BIOS booting. It is also known as “CSM boot” or CSM Enabled. 
  2. UEFI Only booting
  3. Supports both UEFI and Legacy Boot


Storage Disk Drive

A Disk Drive can be any one of the following:

  • Hard disk
  • SSD

GPT Drive Partition Layout required for Windows 10 OS

When UEFI boot mode is used then Microsoft allows installation of Windows 10 OS, only on the disk with the GPT partitioning scheme and there is a certain partition layout required.

GPT Disk partition Layout is required in the following order:

  1. EFI System Partition
  2. Reserved Partition
  3. Partition for Windows 10 OS
  4. Recovery Partition

If these four partitions need to be in a single disk then the GPT disk partition layout must be in order as shown here. I



1. EFI System Partition

The EFI System partition is the first partition in the GPT disk. The minimum size of this partition is 100 MB and must be formatted using the FAT32 file format.

This partition is managed by the operating system. This is where UEFI stores :

  • Boot loaders for all the operating systems installed in the computer. 
  • Device driver files for hardware devices present in a computer and used by the firmware at boot time.

Recommended EFI System Partition size = 500 MB to 1000 MB


2. Microsoft Reserved partition (MSR)

MSR Partition is located just after the EFI System partition and just before the Windows OS partition. In Windows 10, the minimum size of the MSR partition is 16 MB.

An MSR to each GPT drive to help with partition management. The MSR is a reserved partition that does not receive a partition ID. It cannot store user data.

Recommended MSR partition size = 128MB

Currently, this partition has no use and does not hold any data. Still, you should keep this partition.


3. Windows 10 OS partition

Windows OS partition is located just after the MSR Partition and just before the Recovery partition. The NTFS formatted partition in which Windows 10 OS is installed.

4. Recovery Partition

The Recovery partition is located just after the Windows OS Partition. The recovery partition holds the Windows Recovery Environment (Windows RE) tools.

The recovery tools should be in a separate partition other than the Windows partition to support automatic failover and to support booting partitions encrypted with Windows BitLocker Drive Encryption.

We recommend that you place this partition immediately after the Windows partition. This allows Windows to modify and recreate the partition later if future updates require a larger recovery image.

Recommended Recovery Partition Size = 2GB



Partition layout Created by Windows OS during clean install on an Empty Disk

When you clean install Windows 10 on a disk that has no existing partitions then Windows 10 OS installation Setup will automatically create the required GPT partition layout.

If you want the Windows 10 OS installation setup to automatically create the required partition.

  1. The Disk drive in which the windows 10 OS will be installed must not have any existing partitions. 
  2. If there are multiple Disk Drive installed in the computer, then the drives other than the Disk drive in which Windows 10 OS will be installed must not have the following partition:
    1. EFI System partition
    2. Recovery partition







GPT Disk Partition Layout created by the Windows 10 OS Installation media

  1. EFI System Partition (Size = 100MB)
  2. Reserved Partition (Size = 16MB)
  3. Partition for Windows 10 OS ( Size = whatever is left after creating the other three partitions)
  4. Recovery Partition( Size = Around 550MB)



The problem with this layout is that the EFI System partition, Reserved Partition, and Recovery partition size allocated are the minimum. In the future, the free space in these partitions could easily run out, leading to problems related to the purpose for which they were created.


Manually Creating Custom Partition layout for Windows 10 OS clean installation


You can manually create the required GPT disk partition layout using the Diskpart tool.


Note: Make sure you have no user data in the Disk in which Windows 10 OS will be installed.

1. Run the Windows 10 OS installation media
2. When the Windows as shown in the image below shows up click "Repair your computer".




3.   Select "Troubleshoot"



4. Select "Command Prompt"




5. Run the Diskpart tool in the Command Prompt

Command:  diskpart

6. Show the list of disks installed on the computer.

Command: list disk

7. Select the disk in which Windows 10 OS will be installed.


Command: select  disk 0

Note: The disk number may differ in your case. Make sure you select the correct disk number.



8.  Remove all partitions from the selected disk.

Command: clean

9. Converts an empty basic disk partition style to the GUID partition table (GPT) partition style.

Command: convert gpt



10. Create an EFI system partition of size 500 MB. 

  • create partition efi size=500
  • format quick fs=fat32 label="System"





11. Create a Microsoft Reserved (MSR) partition 

  • create partition msr size=128


12. Create a Windows 10 OS partition

  • create partition primary 
  • shrink minimum=2000
  • format quick fs=ntfs label="Windows"
  • assign letter="W"


13. Create a Recovery partition
  • create partition primary
  • format quick fs=ntfs label="Recovery"
  • assign letter="R"
  • set id="de94bba4-06d1-4d40-a16a-bfd50179d6ac"
  • gpt attributes=0x8000000000000001




14. Show the list of partitions in the selected disk.
  • list partition

15. Exit the Diskpart tool
  • exit

These Diskpart commands if executed without error will create all the necessary partitions and the disk will be ready for a clean installation of Windows 10 OS.


16. Close the command Prompt by clicking Close button




17. Select any of the option:
  • Use a device.
  • Turn off your computer





18. Run the Windows 10 OS installation media.



To Fresh install Windows 10 OS on the disk, do the following:
  • When the "Where do you want to install Windows?" shows up, select the third partition in the Disk, which is named "Windows".
  • Click on the Next button for setup to begin installing Windows 10 OS.



Final Partition layout of GPT Disk for Windows 10 OS.









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