A GPT reserved partition can look unnecessary because it has no drive letter or visible files. This guide explains its purpose, distinguishes it from boot and recovery partitions, and shows how to identify it before changing a disk layout. It also covers recovery options when partition deletion leaves a data volume inaccessible or Windows unable to start.
The GPT reserved partition most commonly refers to the Microsoft Reserved Partition (MSR) on a Windows GPT disk. The MSR is a small partition reserved for Windows partition management and future use by system software. It does not store personal files and is not the partition that contains Windows boot files.
Don't confuse the MSR with the EFI System Partition (ESP), which stores UEFI boot files, or a GPT Protective Partition, which relates to how GPT disks are represented to software that may not fully recognize GPT. Identifying the correct partition type is essential before attempting to delete, recreate, or recover any partition.
Both sizes can be normal. Microsoft's current Windows deployment guidance specifies a 16 MB MSR. Older versions of Windows and some setup tools used 128 MB. If you've upgraded Windows or copied an older drive to a new one, the larger MSR may still be there. Before changing anything, check what type of partition it is and how the drive was set up. A 128 MB MSR doesn't need fixing just because a newer Windows installation uses 16 MB.
You may see several small partitions next to C:. They have different jobs, even when they look similar in a disk tool. This table helps you tell them apart.
|
Partition |
Where it belongs and what it does |
What deletion can affect |
|
Microsoft Reserved (MSR) |
On Windows GPT disks; keeps space for disk management; does not store personal files | Later disk management tasks |
|
EFI System Partition (ESP) |
On UEFI boot disks; uses FAT32 and holds the files that start Windows | Whether Windows can start from that drive |
|
System Reserved |
Common on BIOS/MBR Windows PCs; holds startup files and supports BitLocker setups | Windows startup and its boot settings |
|
Windows Recovery |
Holds Windows recovery tools; the PC maker may add separate recovery partitions | Recovery and troubleshooting tools stored on the drive |
If your tool shows a GPT Protective Partition, you're looking at a different situation. You may see it when a disk tool reads the drive’s protective MBR information instead of showing its GPT partitions. This protection helps older tools recognize that the disk is already in use, so they do not mistake it for an empty drive. The displayed area may cover most or all of the disk, rather than a small reserved space.
| What to compare | GPT Reserved Partition (MSR) | GPT Protective Partition |
| What it is | A small partition Windows sets aside for disk management. | A label a disk tool may show when it reads GPT’s protective MBR information. |
| Purpose | Keeps space available for Windows disk management tasks. | Helps prevent older tools from mistaking a GPT disk for an empty drive. |
| Typical size | Usually 16 MB or 128 MB. | May appear to cover most or all of the disk. |
| What you should do | Leave it in place unless a planned layout change requires otherwise. | Check GPT support and disk recognition first. Do not apply MSR deletion commands. |
You can use DiskPart, a command-line tool included with Windows, to find the MSR even when Disk Management doesn't show it. The commands below only check the drive. Replace "N" and "P" with the numbers shown on your own computer.
Step 1: Open DiskPart. Press "Windows" + "R", type "diskpart", and accept the prompt asking for administrator permission.
Step 2: Find the right drive. Run "list disk" and use the drive's size to identify it. An asterisk in the GPT column shows that it uses GPT. Enter "select disk N", replacing "N" with that drive's number.
Step 3: Find the reserved partition. Run "list partition" and look for the entry labeled "Reserved". Enter "select partition P", using its partition number, then run "detail partition" to see more information.
Step 4: Check the partition type. Look for e3c9e316-0b5c-4db8-817d-f92df00215ae. This is the MSR's type identifier, listed in Microsoft's Windows and GPT FAQ. Once you've noted the partition details, enter "exit".
You can delete an MSR partition with the right disk tools, but that doesn't mean you should. The MSR does not store Windows boot files or personal data, and deleting it alone does not necessarily stop Windows from starting. However, removing it changes the disk's intended GPT layout and may complicate later partition management. Since an MSR is usually only 16 MB or 128 MB, deleting it rarely provides a meaningful amount of extra space.
⭐Recommendation: Keep the MSR unless you have a specific, technically justified reason to change the partition layout. If a partition is missing or Windows won't start, identify the affected partition first instead of assuming the MSR is the cause.
Before you make a change, back up first and prepare a way to recover the partition or data if something goes wrong. You can check the following:
If you accidentally deleted the GPT Reserved Partition while managing your partitions, or removed it only to realize you still need it, don't panic. This doesn't necessarily mean all is lost. If your PC starts experiencing problems afterward, you can try the following methods to recover the deleted GPT Reserved Partition.
The MSR contains no personal files or Windows boot files, so recreating it restores reserved space rather than lost data. Before proceeding, confirm that the disk is basic GPT and suitable unallocated space exists in the correct position. Microsoft documents the command for creating an MSR, but the appropriate layout must be verified for your disk.
Step 1. Type "Command Prompt" in the search box and right click on it, then choose "Run as administrator".
Step 2. Enter the following command and press "Enter" key after each one:
Step 3. Once the process is completed, run "list partition" to confirm that a partition with the type "Reserved" appears in the list.
Without an offset, DiskPart creates the partition in the first available extent large enough to hold it. Proceed only if you have verified that this extent is the intended MSR location. If multiple free areas exist or the layout is unclear, stop and have the layout checked before creating the partition.
If Windows stops starting after you delete the GPT Reserved partition, check whether anything else changed too. If you have created a recovery USB or Windows installation media to boot the computer, you can reboot the device and recreate the GPT Reserved partition with the same steps above.
Step 1. Insert the USB installation media and restart your computer, enter BIOS/UEFI (press F2, F12 or Del repeatedly) and change the boot order as the USB.
Step 2. Save the changes and restart your computer. On the Windows installation window, select "Repair your computer" > "Troubleshoot" > "Advanced options" > "Command Prompt" (or press Shift + F10).
Step 3. Then, you can create a new MSR partition on the disk.
During managing the GPT Reserved partition, if other partition has disappeared or its old space now shows as unallocated, MyRecover Professional can help you recover the missing or inaccessible partition along with the files and folders. It offers a Partition Recovery feature that can restore a partition’s files and partition information, including its drive letter, partition table, and file system structure in one step.
Before recovery, stop saving anything to that drive. Don't create a new volume, format it, or reinstall Windows over it. For an SSD, recovery also depends on TRIM, blocks already erased by this feature can't be guaranteed recoverable.
Step 1: Install MyRecover away from the affected drive. Download MyRecover for Windows and install it on a healthy drive. Installing software on the affected drive could overwrite data you're trying to recover.
Step 2: Choose the drive to scan. Run the application and select "Partition Recovery", identify the drive that contained the missing partition by its size and model, and click "Next".
Step 3: Look for the missing partition. Choose "Fast Search" or "Full Search" and click "Next". If Fast Search doesn't find the partition you expect, try "Full Search". This checks more of the partitions on the drive and takes longer.
Step 4: Check the partition it finds. Compare its file system, size, and start and end sectors, which show its position on the drive, with the original partition. Select the matching partition and click "Proceed".
When recovery finishes, open the drive you expected to get back in File Explorer and check whether the files and folder structure on the partition have been restored to their original state.
If your drive works normally, leave the GPT reserved partition in place. In most cases, deleting it will not free up a significant amount of disk space. If you've already deleted it, you can create a new one using the command line tool.
When a data partition is missing or won't open, choose a reliable recovery method like MyRecover to get your files and partition back. For IT teams handling recovery across a company's computers, MyRecover Technician allows unlimited use within that company. It supports data and partition recovery, including through bootable media when Windows won't start.
Does every Windows GPT disk need an MSR partition?
Yes, Windows expects an MSR on every GPT disk it manages, even a drive used only for your files. It keeps a little space available for disk management. This is a Windows requirement; other operating systems may use different layouts. A data-only disk generally doesn't need an EFI partition.
Why can't I see the MSR partition in Disk Management?
Disk Management doesn't show the MSR as a regular drive, so you may not see it there. Open DiskPart and use "list partition", then "detail partition", to check for it. Being absent from Disk Management doesn't mean it's been deleted, and you shouldn't format it to make it appear.
Does a GPT reserved partition contain personal files?
No, the Microsoft Reserved Partition doesn't store your documents, photos, or other personal files. Those belong on Windows or data partitions. If files went missing after you deleted a partition, check whether another partition was affected too.
Is a 128 MB MSR partition normal?
Yes, 128 MB can be normal if the drive was set up with an older Windows layout or setup tool. Newer Windows guidance uses 16 MB, but an upgrade or copied drive may keep the larger MSR. You don't need to resize it just to match the newer size.
Can I recreate an MSR partition without reinstalling Windows?
Yes, if the other partitions are intact and there's enough unallocated space in the right place, you can recreate the MSR without reinstalling Windows. Recreating this small partition won't bring back deleted personal files or fix the EFI startup files.
Will deleting the MSR partition prevent Windows from booting?
Not necessarily. If you deleted only the MSR, Windows may still start because its UEFI startup files are on the EFI System Partition. Even so, deleting the MSR isn't recommended. If Windows won't start afterward, check whether another partition was affected and recover needed files before further repairs.
Can MyRecover bootable media recover partitions when Windows won't start?
Yes, you can use a MyRecover bootable USB to run data and partition recovery when Windows won't start, as long as the PC can start from the USB and read the affected drive. It doesn't fix Windows startup. Make the USB on a working computer first.