How to Remove the System Reserved Partition on BIOS/MBR Windows Systems

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During a clean installation of Windows on an MBR disk, the installer creates a small NTFS partition at the beginning of the system disk, called the System Reserved Partition (SRP). The System Reserved partition is usually between 100 MB and 500 MB in size, depending on the Windows version and installation method. In this post we’ll explain that the System Reserved Partition is used in Windows for, and how you can hide or remove it.

What is System Reserved Partition in Windows

Open the Disk Management snap-in (diskmgmt.msc) and locate a small system reserved partition in front of the system C: drive with the System and Active attributes. By default, it has no assigned drive letter.

On BIOS or UEFI-based computers

On BIOS-based systems (or UEFI systems booting in Legacy/CSM mode), Windows creates a System Reserved Partition. On UEFI/GPT systems, the OS typically uses an EFI System Partition (ESP) instead of a System Reserved Partition.

• Bootloader files (bootmgr) — boot manager used to start Windows OS
• The Boot Configuration Data (BCD) store — boot configuration parameters to launch Windows
• BitLocker files for pre-boot authentication and unlocking the encrypted drive (if BitLocker is used to encrypt the system drive)
• Windows Recovery environment (WinRE) image (in some cases)

As you can see, SRP contains a number of important system files that are required to boot Windows on a computer. The boot loader files are stored on this partition. If you delete it, Windows won’t boot properly.

Cases in which it is safe to delete the System Reserved partition

The only cases in which it is safe to delete the System Reserved partition are as follows:

• You have moved the Windows boot loader (bootmgr) and BCD files to the system disk (which contains Windows).
• The BitLocker drive encryption feature is not enabled for the system drive.
• On disks that are no longer used to boot Windows (and the SRP is not used anymore).
• After converting your system drive to UEFI with GPT.

Deleting the System Reserved partition makes no sense in most cases, since its size is not large and deleting it will not add a significant amount of free space. It may be enough for you to hide it if it shows up in Explorer with an assigned drive letter.

How to Hide the System Reserved Partition in Windows

If the File Explorer shows a separate drive labeled System Reserved, you can hide it from users.

1. Open the Disk Management MMC snap-in (diskmgmt.msc).
2. Right-click the System Reserved partition on the system disk and select Change Drive Letter and Paths.
   

   

3. Remove the drive letter assigned to this system partition.
   

   

4. After that, SRP will no longer appear in the File Explorer.

Removing System Reserved Partition with DISKPART

If you want to completely remove the System Reserved partition from the disk, you must first move all the necessary Windows bootloader files to the system drive. We will use the DISKPART command to delete the System Reserved Partition. DISKPART is a command-line tool built into Windows that lets you manage disk partitions.

Boot the computer from the bootable media. This can be a LiveCD with the WinPE environment or a USB drive with the Windows 10 or 11 installation image (in our case).

1. On the initial Windows Setup screen, press Shift + F10 to open the command prompt.
2. Type diskpart and press Enter.
3. List volumes with labels: list vol (in this case, the SRP partition is located on Volume 1, labeled System Reserved, and is 50MB in size).
   Don’t forget to check the drive letter assigned to the Windows partition in WinPE before running BCDBoot commands. The drive letter may differ from the one used when Windows is running normally.
   

   

4. List available disks:
   

   list disk
   sel disk 0

5. List partition on the disk:
   

   list part

6. The system reserved partition on the disk has the Partition number 1.

   

7. Select the Windows partition and mark it as the active boot partition:

   sel part 2
   active

   Note that on BIOS/MBR systems, the active partition flag determines which partition the firmware will attempt to boot from.

8. Exit the DISKPART session:
   

   exit

9. Recreate the Windows boot files and BCD store on the Windows partition. In this example, the Windows partition is assigned the drive letter D: in WinPE:
   

   bootrec.exe /fixmbrbootsect.exe /nt60 all /forcebcdboot D:\Windows /S D:

10. Restart the computer and verify that Windows boots successfully.
    

    A successful BCDBoot operation only confirms that the boot files were created. It does not guarantee that Windows can boot correctly using the new config.Restart the machine and check if Windows starts normally before removing the System Reserved partition:

    wpeutil reboot

11. Boot back into WinPE.
    

    After confirming that Windows boots successfully without relying on the System Reserved partition, you need to boot again from your Windows installation media/WinPE environment, then press Shift + F10 to open Command Prompt, and start DISKPART with the command:

    diskpart

12. Select the disk and delete the System Reserved partition:
    Warning. The del part override command permanently removes the System Reserved partition! You must ensure that the boot files have been successfully recreated on the Windows partition before deleting it.
    

    list disk
    sel disk 0
    
    list part
    sel part 1
    
    del part override

    
13. Confirm that the System Reserved partition has been removed:
    

    list vol

14. Exit the DISKPART session:
    

    exit

    
15. After removing the System Reserved partition, you can extend the adjacent Windows partition and use the unallocated space that was freed.

Now you can merge the unallocated space left after removing SRP with the main partition.

The System Reserved partition is a critical area on the operating system disk and cannot be removed while booted into Windows. Removing the System Reserved partition is only possible on non-active operating system disks.