Solved: Windows Update Error 0x80070643 (Update Failed to install)

Microsoft recently released Windows 10 KB5034441 security update that patches the CVE-2024-20666 BitLocker vulnerability that allows attackers to access encrypted data. However, while attempting to install the update users report Windows 10 update Install error – 0x80070643. After the system restart, the Windows Update screen stating that an error occurred and to try again later.

“There were some problems installing updates, but we’ll try again later. If you keep seeing this and want to search the web or contact support for information, this may help: (0x80070643),” reads the Windows Update error.

How to fix Windows 10 Update Error 0x80070643

Well, Microsoft acknowledged this error 0x80070643 causing when installing the Windows 10 KB5034441 security update, and its support website recommends manually resizing your partition to install the WinRE update and fix the problem.

This update requires 250 MB of free space in the recovery partition to install successfully. If the recovery partition does not have sufficient free space, this update will fail. 0x80070643 – ERROR_INSTALL_FAILURE 

How to Manually resize your partition to install the WinRE update

Here are Microsoft instructions on how to manually resize your partition to install the WinRE update that helps fix Windows update error 0x80070643 – ERROR_INSTALL_FAILURE. Hence, this workaround involves resizing partitions, it is advised to create a system backup before making any changes.

First, open the command prompt with administrator privileges. Press Windows key + S and type cmd, Right click on the command prompt select run as administrator.

• Type the command reagentc /info and press the enter key to check if the WinRE is installed on your device.
• Next, we need to temporarily disable WinRE using the command reagentc /disable

• Now to Shrink the OS partition and prepare the disk for a new recovery partition, we need to run diskpart command, then list disk.
• Select the OS disk using command select disk<OS disk index>  This should be the same disk index as WinRE. For me the command is select disk 0
• To check the primary partition under the OS disk and find the OS partition, run list part command.

Next, select the OS partition (primary partition), run sel part<OS partition index> For me its select partition 3 

Next, we need to shrink that partition to do this Run the command shrink desired=250 minimum=250 command. This will shrink the primary partition by 250 MB,

Then run command sel part<WinRE partition index> To select the WinRE partition. for me, it is sel partition 4 (select the recovery one) and delete the WinRE partition 4 using the command delete partition override. This will delete the partition 4, which is your recovery partition. (don’t worry we are going to create a new one)

Let’s Create a new recovery partition, to do this First, check if the disk partition style is a GUID Partition Table (GPT) or a Master Boot Record (MBR) using command list disk.

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

You will see the disk partition successfully assigned the attributes to the selected partition.

Next we have to format that created partition, To format the partition, run format quick fs=ntfs label=”Windows RE tools”

Again run list vol command to confirm that the WinRE partition is created, then type exit to leave disk part.

Run reagentc /enable command to re-enable WinRE, and to confirm where WinRE is installed, run reagentc /info

That’s all, restart your computer and check for Windows updates to try install the Windows 10 KB5034441 security update again.

Also recently Microsoft has released PowerShell script that automate the installation of the BitLocker CVE-2024-20666 security patch to the Windows 10 Windows Recovery Environment (WinRE).

In addition to above workaround, you can also try following troubleshooting steps to fix Windows update installation error on your computer.

Run Windows Update Troubleshooter

The built-in Windows Update Troubleshooter from Microsoft automatically diagnose and fix common update problems. It scans your system for issues and attempts to resolve them, making it an easy first step in troubleshooting update errors.

• Open Settings by pressing the Windows key + I.
• Go to Update & Security then Troubleshoot from the left sidebar.
• Click on Additional Troubleshooters, Scroll down and select Windows Update.
• Click on Run the troubleshooter and follow the on-screen instructions.

Free Up Disk Space

Windows updates require sufficient free space on your hard drive to download and install. If your disk is full, the update process may fail. Delete unnecessary files, such as temporary files and old downloads, or move large files to an external drive to free up space.

• You can run Disk clean up tool to scan temporary files, Internet cache files, and unnecessary program files that you can safely delete. Uninstall unused programs from the Control Panel.
• Try to move large size files and folders to external storage to free up the system drive on your computer.

Reset Windows Update Components

Over time, Windows Update components may become corrupted or misconfigured, leading to update errors. Resetting these components can often fix the problem.

• Press Windows key + R, type services.msc and click ok,
• On the services window locate Windows Update, right click on it select stop.
• Now press Windows key + E to open file explorer, nevigate C:\Windows\SoftwareDistribution\Download
• Here delete all files and folders inside the download folder, press Ctrl + A to select all then hit del key.
• Now restart your compteur and try to install windows update again.

Run SFC and DISM command

Sometimes Corrupted system files are the reason behind Windows update failures or error messages. Running the System File Checker (SFC) and Deployment Image Servicing and Management (DISM) commands can help repair these files and restore the integrity of your system.

Open command prompt as administrator,

First run system file checker command sfc /scannow, this will scan your system files for any corruption and attempt to repair them automatically.

In addition, run DISM /Online /Cleanup-Image /RestoreHealth command this will attempt to repair the Windows image by downloading and replacing any corrupted files from Windows Update.

Once the scanning is complete, restart your computer and try running Windows Update again.

Hope this helps fix Windows 10 update Install error – 0x80070643.