Help installing KB5034441 after error 80070643 (2024)

• Network Admin

It is rare for MS to issue an update that requires a lot of manual intervention, but KB5034441 is one. After much frustration (involving bitlocker and 48-character recovery codes!) I found a set of instructions which worked for me.

In order of preference, you should:

1. First try expanding the recovery partition. It needs 250MB free space to work with the new update.
   • Open elevated Command Prompt (CMD) and check your recovery partition info by running “reagentc /info”. Note which partition is your recovery partition. If the recovery partition status is Enabled then you need to disable it.
   • Run “reagentc /disable”
   • Run “diskpart”
   • Run “list disk” (take note if there is a * under the GPT column; we will use this knowledge later.)
   • Switch to the disk where the operating system is installed by running “Select Disk x” where x is the disk #.
   • Run “list partition” and look at which one is the ‘Primary’ partition. This is the one we will shrink to make space for the recovery partition.
   • Switch to that partition by running “Select partition x” where x is the Primary partition #.
   • Run “shrink desired=250 minimum=250”
   • Switch to the Recovery partition by running “Select partition x” where x is the recovery partition #.
   • Run “delete partition override” to DELETE the recovery partition. Please be sure you are on the correct partition before you do this.
   • Rebuild the recovery partition (select one):
     • If there was a * under GPT then you rebuild by running this command: “create partition primary id=de94bba4-06d1-4d40-a16a-bfd50179d6ac” and ENTER. Then run this command: “gpt attributes =0x8000000000000001” and ENTER.
     • If there was no * under GPT then you have an MBR disk, and you may rebuild by running this command: “create partition primary id=27”
   • Format the new partition: Run this command: “formatquick fs=ntfs label=”Windows RE tools””
   • Run “list vol” command to see if the recovery partition was created successfully.
   • Run “exit” to get out of disk part utility.
   • Run “reagentc /enable” and then check it with “reagentc /info” and if it looks good then reboot your PC and Check for Updates again.
     The source for this fix and a good resource if you want photos of each step is this website: This Is How I Fixed the Windows Update Error 0x80070643 (howtogeek.com)Many people report this does not fix the install error. Some try some PowerShell commands (i never tried this) or disable and reenable Bitlocker (giant pain) or the TPM (giant pain) or install a tool which allows you to hide updates (ha!), and you’re welcome to explore those routes. Or, at this point you may be thinking “Why am I suffering for an obsolete OS like Win10?” Right you are. But from what I read it could be an issue on 11 as well so you might as well see this thing through! Moving on….
2. Overwrite your old recovery environment files.
   In this step we will download a copy of your OS, extract the windows recovery environment files and copy to your system.
   You can use the steps published here: Fix for KB5034441 that keeps failing : r/WindowsUpdate (reddit.com)OR…if that’s not available, here is a copy of the steps:
   • Use a program like Veeam, Macrium or Acronis to backup your PC before continuing. Not that these steps are very unlikely to cause any system issues, but they do include altering system files, so better be safe than sorry.
   • Open CMD as Admin and writereagentc /infoto determine if Windows RE is enabled or not. If it’s already disabled, continue, otherwise, writereagentc /disableto disable it
   • Go to theWindows siteand download the corresponding Tool for your system
   • Open the Tool and choose “Create Installation Media” > Next > ISO file > download the ISO file somewhere on your C-drive, e.g.C:\ISO\> Mount the ISO-file in Explorer > Take note of the Drive Letter (e.g. E:)
   • Go back to CMD and write:DISM.exe /Get-ImageInfo /ImageFile:[Drive Letter]:\sources\install.esd /Index:1
   • Write in CMD:DISM.exe /Export-Image /SourceImageFile:[Drive Letter]:\sources\install.esd /SourceIndex:1 /DestinationImageFile:C:\install.wim /Compress:fast /CheckIntegrity
   • Create a new dir:C:\MountDir
   • Write in CMD:DISM.exe /Mount-Wim /WimFile:C:\install.wim /index:1 /MountDir:C:\MountDir /ReadOnly
   • Open C:\MountDir\Windows\System32\Recovery\and copy bothReAgent.xmlandWinre.wim.Paste both files in a new directory somewhere else, as these files will be used later.
   • Write in CMD:DISM.exe /Unmount-Wim /MountDir:C:\MountDir /discard. This will empty the directory and unmount the DISM image.
   • Delete the foldersC:\MountDir, C:\ISO(unmount first) and the fileC:\install.wim.
   • Copy the two files from the directory you copied them to earlier, and paste them intoC:\Windows\System32\Recovery\. Replace the file(s) if they already exists.
   • Write in CMD: reagentc /enable
   • Attempt to run a Windows Update again, and this time it should install the KB5034441 update.