Windows update (KB5034441) Error (0x80070643)

Done this fix twice. Certainly had no issues following along.

All it does is delete the recovery partition shrinks the c drive and increases the recovery partition when it's recreated by 250mb.

I don't see how this could cause a problem unless people are not very good at following instructions.

That's my opinion.

Looks like Microsoft pulled this message, as it "usually" does NOT work and can cause some serious problems.

For those who do not have reagentc working (missing files) it is pretty hard to get reagentc enabled without a complete reinstall of Windows (complete file loss). Could copy the WinRE files from a PC that has the exact same version of Windows 10 with this Update completed successfully, and move the files to the PC that does not have the needed files. These are boot.sdi, ReAgent.xml, and most important winre.wim. My advice is NOT to do this.

You can use Command Com (Admin) or Partition software to create and copy these files or partition to the problem PC and then run Windows Recovery and have Windows find the files. This just might work. I hope MS fixes this, but no matter it does not affect operation. Just completed the Windows 2024-02 Cumulative Update Preview for Windows 10 Version 22H2, released today, and it did not fix this error.

Folks, here's the skimmy on this. Beside this update being necessary only for those PC's with a WinRE partition, Win10 end-of-life is October 2025.

**Summary**

Microsoft has changed how it updates PCs that run the Windows Recovery Environment (WinRE). WinRE will be updated using the monthly cumulative update. This change only applies to PCs that get updates from Windows Update (WU) and Windows Server Update Services (WSUS). This change starts on June 27, 2023, for the Windows 11, version 22H2 cumulative update.  

Some PCs might not have a recovery partition that is large enough to complete this update. Because of this, the update for WinRE might fail. You will receive the error message, "Windows Recovery Environment servicing failed.” To help you recover from this failure, this article provides instructions to manually resize your recovery partition if you get a system ErrorPhase of 2. This requires your device to have the recovery partition after the OS partition. Use the steps below to verify this.    

Manually resize your partition by 250 MB

1. Open a Command Prompt window (cmd) as admin.
2. To check the WinRE status, run 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. To disable the WinRE, run reagentc /disable
4. Shrink the OS partition and prepare the disk for a new recovery partition.
5. To shrink the OS, run diskpart
6. Run list disk
7. To select the OS disk, run sel disk<OS disk index>  This should be the same disk index as WinRE.
8. To check the partition under the OS disk and find the OS partition, run list part
9. To select the OS partition, run sel part*<OS partition index>*
10. Run shrink desired=250 minimum=250
11. To select the WinRE partition, run sel part*<WinRE partition index>*
12. To delete the WinRE partition, run delete partition override
13. Create a new recovery partition.
14. 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.
15. If your disk is GPT, run create partition primary id=de94bba4-06d1-4d40-a16a-bfd50179d6ac followed by the command gpt attributes =0x8000000000000001
16. If your disk is MBR, run create partition primary id=27
17. To format the partition, run format quick fs=ntfs label=”Windows RE tools”
18. To confirm that the WinRE partition is created, run list vol
19. To exit from diskpart, run exit
20. To re-enable WinRE, run reagentc /enable
21. To confirm where WinRE is installed, run reagentc /info

**Note** If creation failed or you do not want to extend the WinRE partition, run reagentc /enable to re-enable WinRE.

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