Windows 11 not updating to Windows 11 Insider Preview Feature Update (26220.7051)

- Fixing Windows 11 Insider “Fix Issues” / “Reserved Partition Can’t Be Updated” Error (Full EFI Method)

If you get the “Fix issues” or “Reserved partition can’t be updated” message when trying to install a Windows 11 Insider Preview Feature Update, it usually means your EFI (System Reserved) partition is too small — typically 100 MB.

This guide shows how to create a new, larger EFI partition, make Windows boot from it, and safely remove the old one.

- Step 1 – Create a new EFI partition

Open Disk Management.

Shrink any existing partition to free about 1 GB of unallocated space.

Create a new partition, format it as FAT32, and label it EFI_New.

Assign it a drive letter (for example, S:).

- Step 2 – Copy boot files to the new EFI

Open Command Prompt as Administrator and run:

bcdboot C:\Windows /s S: /f UEFI

This copies the necessary boot files to the new EFI partition.

- Step 3 – Point Windows Boot Manager to the new EFI

Run these commands (replace the X with the correct volume number for your new EFI, check it using diskpart → list volume):

bcdedit /set {bootmgr} device partition=HarddiskVolumeX

bcdedit /set {bootmgr} path \EFI\Microsoft\Boot\bootmgfw.efi

- Step 4 – Verify that Windows now uses the new EFI

bcdedit /enum all | find "device"

Check that {bootmgr} and osdevice now point to your new EFI partition (e.g. partition=S:).

- Step 5 – Delete the old EFI partition

Reboot into Windows Recovery (Shift + Restart → Troubleshoot → Advanced options → Command Prompt).

Run DiskPart:

diskpart

list disk

select disk 0

list partition

select partition 1

delete partition override

exit

Delete the old 100 MB EFI partition only after confirming the system boots properly from the new one.

- Step 6 – Run Windows Update again

Now run Windows Update.

The Insider Feature Update (like build 26220.7051) should install normally — no more “Fix issues” or “Reserved partition can’t be updated” errors.

Tips

• Always back up your BCD before making changes:

bcdedit /export C:\BCD_Backup

To restore:

bcdedit /import C:\BCD_Backup

• Double-check partition numbers before deleting anything.

• You can verify the active boot partition any time using bcdedit /enum all.

Result

Your PC now boots from the new EFI partition, has enough reserved space for future Insider updates, and the Windows Update problem is permanently solved.

🤗