Since the beginning of the year, numerous Windows 10 users have encountered issues installing security update KB5034441, receiving the error code 0x80070643. Microsoft has recently stated that it will no longer pursue an automated fix for this problem. Instead, users will need to manually increase the size of their WinRE partition to facilitate the successful installation of this update.
“An automatic solution will not be included in future Windows updates. Manual intervention is necessary to install this update on affected devices,” Microsoft noted in their latest announcement on April 30.
Previously, Microsoft had indicated that a resolution was forthcoming in a future update. The company has not explained the change in approach.
Manual adjustment required
The update KB5034441 addresses a security flaw in Windows 10 (CVE-2024-20666) that could compromise Bitlocker encryption through the Windows Recovery Environment (WinRE). However, the installation process for many users fails due to an error coded as “0x80070643 – ERROR_INSTALL_FAILURE”.
Microsoft attributes this installation failure to insufficient space in the WinRE partition, which needs at least 250 MB of free space to install KB5034441 properly. Users affected by this issue are now required to expand this partition manually.
To facilitate this, Microsoft has released a PowerShell script that increases the WinRE partition by 250 MB. Alternatively, users can find manual instructions on adjusting the partition size in the Microsoft support section.
For users whose systems do not have WinRE configured, Microsoft advises disregarding the error code 0x80070643, as the update KB5034441 is unnecessary in such cases. To verify the configuration, users can type “reagentc /info” into an admin console. If the “WinRE status” appears as “Enabled”, then the recovery environment is active on the system.
