Fix Windows 10 Update KB5034441 Error 0x80070643

The reason KB5034441 failed to install with error 0x80070643 is that there is not sufficient space in WinRE recovery partition. The solution is:

Manually resize your WinRE recovery partition by 250 MB

1. Open a Command Prompt window (cmd) as Administrator.
2. Check WindowsRE status:

   reagentc /info

   
   If the WinRE is installed, there should be a “Windows RE location” with a path to the WinRE directory. An example is, “Windows RE location: [file://%3f/GLOBALROOT/device/harddisk0/partition4/Recovery/WindowsRE]\\?\GLOBALROOT\device\harddisk0\partition4\Recovery\WindowsRE.” Here, the number after “harddisk” and “partition” is the index of the disk and partition WinRE is on.
3. Disable the WindowsRE:

   reagentc /disable

4. Shrink the OS partition and prepare the disk for a new recovery partition.
   • Run

     diskpart

   • Run

     list disk

   • Select the OS disk (This should be the same disk index as WinRE.), run

     sel disk OS_DISK_INDEX

     e.g.

     sel disk 0

     if disk 0 is the OS disk.
   • Find the OS Primary partition, run

     list part

   • Select the OS Primary partition, run

     sel part OS_PARTITION_INDEX

   • Shrink the OS Primary partition by 250MB, run

     shrink desired=250 minimum=250

5. Delete the WinRE recovery partition
   • In diskpart, select WinRE partition, run

     sel part WinRE_PARTITION_INDEX

   • Delete the WinRE partition, run

     delete partition override

6. Create a new WinRE recovery partition.
   • First, check if the disk partition style is a GUID Partition Table (GPT) or a Master Boot Record (MBR). To do that, run

     list disk

     . Check if there is an asterisk character (*) in the “Gpt” column. If there is an asterisk character (*), then the drive is GPT. Otherwise, the drive is MBR.
   • If your disk is GPT, run

     create partition primary id=de94bba4-06d1-4d40-a16a-bfd50179d6ac

     followed by the command

     gpt attributes =0x8000000000000001

   • If your disk is MBR, run

     create partition primary id=27

7. Format the new WinRE recovery partition, run

   format quick fs=ntfs label="Windows RE tools"

   
   To confirm that the WinRE partition is created, run

   list vol

   
   Exit from diskpart, run

   exit

8. Re-enable WinRE, run

   reagentc /enable

   
   To confirm where WinRE is installed, run

   reagentc /info

Now you should be able to install KB5034441 via Windows Update

See also

• The January 2024 Windows RE update might fail to install
• Script to Extend the Windows RE Partition
• KB5028997: Instructions to manually resize your partition to install the WinRE update
• A Youtube video shows how to this 0x80070643 error