Windows 10 22h2 security update [KB5034441] fails to install with code: 0x80070643

Yeah - this tripped me up too. Turns out that when you follow their instructions, the quick format re-assigns the partition ID. Since I'm using MBR, the quick format changed it from 27 (recovery partition) to 07 (ntfs partition). Because of this, reagentc couldn't find it - and I couldn't point it at the new partition either.

I had to use DISKPART to set the ID back to 27 after I quick formatted it. I imagine you'd have to do something similar if your drive is GPT, but I can't test it. After that, reagentc worked properly, the update installed correctly, and my system has been fine.

I didn't had to.
I didn't resize it even, it was 2GB+ by default.

C:\WINDOWS\system32>reagentc /info

Windows Recovery Environment (Windows RE) and system reset configuration

Information:

Windows RE status:         Enabled 

Windows RE location:       \\?\GLOBALROOT\device\harddisk2\partition1\Recovery\WindowsRE 

Boot Configuration Data (BCD) identifier: 6cd92040-3fa9-11ea-a053-ce4b053997f7 

Recovery image location: 

Recovery image index:      0 

Custom image location: 

Custom image index:        0 

REAGENTC.EXE: Operation Successful.

Details for image : \?\GLOBALROOT\device\harddisk2\partition1\Recovery\WindowsRE\winre.wim

Index : 1

Name : Microsoft Windows Recovery Environment (x64)

Description : Microsoft Windows Recovery Environment (x64)

Size : 2,347,976,762 bytes

WIM Bootable : No

Architecture : x64

Hal : <undefined>

Version : 10.0.19041

ServicePack Build : 1

ServicePack Level : 0

Edition : WindowsPE

Installation : WindowsPE

ProductType : WinNT

ProductSuite :

System Root : WINDOWS

Directories : 3614

Files : 17575

Created : 07-Dec-19 - 9:11:48

Modified : 12-Aug-20 - 3:21:21

Languages :

en-US (Default)

At least this method actually works and the update was successful afterwards. But come on MS, do people really should use diskpart for just an update...

Be careful with this!!

Since I have an MBR drive like you - when I followed these steps as you notated:

Then. still within DISKPART, since my disk-drive uses MBR,

I entered the command: create partition primary id=27

and then,k to format the partition, format quick fs=ntfs label=”Windows RE tools”

and then exit.

The quick format re-assigned the id of my new recovery partition to 07, instead of the 27 that the Restore Partition needs, and that you set above. This meant that when I turned the restore back on with reagentc /enable, the computer couldn't find the restore partition I had just created.

You should check to make sure that your new partition is actually a restore partition - a quick way to check it is to look at it in the Disk Management tool.

To fix it, I had to add an extra step - what I'm calling 5c:

5c. If your disk is MBR, run set id=27

You should now see the partition type as a "Recovery Partition" if you look in Disk Management.

Hope this helps!