The "System Reserved Partition (SRP)" (also known as "EFI System Partition (ESP)") is a small partition in Windows (~100MB) that is automatically created during Windows 11 installation and contains the necessary Boot Configuration Data (BCD) to start Windows.
However, on some laptops with Windows 11 preinstalled by the manufacturer, the reserved system partition is also used to store the BIOS update files or a BIOS backup, resulting in insufficient free space to update Windows 11 from v23H2 to v24H2, causing the errors "0xc1900201" or "0x800f0922" with the error message: "We couldn’t update system reserved partition".
How to fix errors 0x800f0922 & 0xc1900201 in Windows 11 24H2 update (We couldn’t update System Reserved Partition).
As you can understand from the above, the solution to fix the "0xc1900201" or "0x800f0922" errors in Windows 11 24H2 update is to either free up space on the system reserved partition, increase its size, or perform a clean install of Windows 11 v24H2.
- Delete Fonts Files on EFI System Partition (System Reserved Partition).
- Resize EFI System Partition (System Reserved Partition).
- Clean Install Windows 11.
Method 1. Free up space on the System Reserved Partition by Deleting Font files.
The first and easiest method to solve the error 0xc1900201 in Windows 11 24H2 update, is to free up space on the System Reserved Partition (aka "EFI System Partition") by deleting the font files stored on it.
1. In Search type "cmd" and then open Command Prompt as Administrator.
2. In command prompt, give the following commands in order (press Enter after typing each command):
- mountvol y: /s
- Y:
- cd EFI\Microsoft\Boot\Fonts
- del *.*
After typing the last command press Y and then Enter to continue.
3. Restart your PC and try to install the update(s) again.
Method 2. Expand the Size of EFI System Partition (aka "System Reserved Partition")
The second method to solve the error 0xc1900201 in Windows 11 24H2 update (which is the permanent fix of the issue), is to increase the size of the System Reserved Partition, using a Free Partitioning tool, like AOMEI Partition Assistant.
Step 1. Install AOMEI Partition Assistant (FREE)
1. Download the freeware version of AOMEI Partition Assistant Standard.
2. When the download is completed double-click at the downloaded file to start the installation.
3. At the next screen click Skip and then click Install Now to install the free edition of AOMEI Partition Assistant Standard.
Step 2. Resize EFI System Partition with AOMEI Partition Assistant.
To increase the size of the EFI System Partition (aka "System Reserved Partition"):
1. Open AOMEI Partition Assistant.
2. Select the drive C: and click Resize/Move Partition from the sidebar on the right.
3. On the next screen, select the option I need to move this partition and then click on the two arrows next to 'Partition size'.
4. Now, click the Down arrow next to the "Partition Size" field to reduce the size of the main C: drive by ~200 MB and assign this space to "Unallocated space after" field as in screenshot below.
5. Then, click and hold your mouse on the C: drive space and drag your mouse to the right, until all the allocated space goes from the "Unallocated space after" to the "Unallocated space before" field as in screenshot below. When done, click OK.
6. At this point, an Unallocated space should have been created between the Microsoft Reserved Partition and the C: drive, as in screenshot below. If so, continue to the next step, otherwise close AOMEI Partition Assistant without applying changes and start from scratch.
7. Now, select the Microsoft Reserved Partition and click Resize/Move Partition.
8. Click on the "16.00MB" square and, holding down the left mouse button, drag the square all the way to the right.
9. When done, click OK
10. At this point, the Unallocated space should have moved between the FAT32 – EFI System Partition and the Microsoft Reserved partition, as in the screenshot below.
11. Now select the FAT32 – EFI System Partition and click Resize/Move Partition.
12. Now click on the right side of the rectangle, then hold down the left button and drag the slider all the way to the right to select all the available capacity.
13. When done, click OK.
14. At this point, the FAT32 – EFI system partition will have "grown" by about 200 MB. Click Apply to apply the change.
15. Then press Proceed on "Pending Operations" window to continue.
16. Finally, click OK to Restart into PreOS mode.
17. After the restart, you will see a DOS window showing the changes that AOMEI Partition Assistant is applying, and once this happens the computer will restart once more to apply all the changes. Once this done, the computer will boot normally into Windows.
18. After entering Windows, open AOMEI Partition Assistant again to verify that the size of the EFI system partition has been increased.
19. When done, close the AOMEI Partition Assistant and proceed to update your system again.
Method 3. Clean Install Windows 11.
The final method to fix the error codes 0xc1900201 & 0x800f0922 on Windows 11 24H2 update, is to backup your files and to perform a fresh installation of Windows. For this task, read the instructions in the following article: