By Bryce / Last Updated November 1, 2022

About “We couldn't update the system reserved partition”

When you upgrade to Windows 10 from Windows 8.1 or Windows 7, the upgrade may fail with the following error message: "We couldn't update the system reserved partition". It may also come with error code: 0x800F0922 or other errors.

Couldnt Update System Reserved Partition

Why is it unable to update system reserved partition?

This Windows 10 upgrade error is usually caused by insufficient space on the system reserved partition. When you install Windows to a partitioned MBR disk, Windows will create an additional partition without a drive letter, but labeled as system reserved, which stores important boot files and normally locates before the system partition (often known as C: drive).

On Windows 7, it often takes 100MB disk space, 350MB on Windows 8, and 500MB on Windows 10. Since upgrading to Windows 10 needs more space on the system reserved partition, Windows 10 will not upgrade successfully unless it detects that the system reserved partition has enough space.

If you fresh install Windows 10 to a specific partition, you won't receive this error. By the way, the system reserved partition first appearance was on Windows 7, so you won't have this error on previous versions of Windows.

Solve it easily with 5 steps

To solve this problem of "We couldn't update the system reserved partition", you can increase the size of system reserved partition using the free partition software called AOMEI Partition Assistant Standard. With it, you can shrink another partition to get some unallocated space and add it to the small system reserved partition, resize BitLocker partition, create/delete/wipe/merge partition, and so on. You can download this freeware and take a look at the detailed steps.

Download Freeware Win 10/8.1/8/7/XP
Secure Download

Step 1. Right-click on the partition you want to shrink and select "Resize Partition". You can select C: drive or the drive after it. Here we take D: partition for example. Right click it and choose “Resize Partition”.

Resize D

Step 2. In the pop-out window, drag the slider bar from left to right. You can also enter the specific amount of space you want to shrink.

Shrink D

Step 3. Right-click C drive and select "Resize Partition". Drag the C: drive rightward to make the unallocated space next to system reserved partition.

Resize C

Move C

Step 4. Right-click system reserved partition and select "Resize Partition". In the pop-out window, drag the slider bar rightward to extend it into unallocated space.


Step 5. Click "Apply" to execute the process.


▸The program will need to restart your computer to complete these operations under PreOS Mode. You can also create a bootable media with AOMEI Partition Assistant to complete the process.
▸If your C drive is large enough, you can also shrink C drive first to get unallocated space for extending system reserved Partition. That will shorten the whole process.


After increasing the system reserved Partition size, you should be able to upgrade Windows 7 or Windows 8 to Windows 10 without receiving "we couldn't update the system reserved partition" error. If you want this to be even easier done, you can use AOMEI Partition Assistant Professional to simply allocate free space from any other partition to system reserved partition. Only three steps can make it done.

Moreover, after upgrading to Windows 10, you can still use AOMEI Partition Assistant to migrate OS to SSD, clone disk, and convert disk between MBR and GPT, etc as it supports Windows 10/8.1/8/7/XP/Vista.