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Every day since the last Patch Tuesday (effectively a Wednesday for me), which has now been a week, Reliability Monitor has been listing the following error: "Installation Failure: Windows failed to install the following update with error 0x80240017: 2026-09 Extended Security Updates (ESU) Licensing Preparation Package for Windows 10 Version 22H2 for x64-based Systems (KB5126256)." Why has this been happening and how can it be remedied?
(Environment: Windows 10 Home version 10.0.19045 Build 19045; not ESU-enrolled.)
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Hi, I'm Bernard. I'm happy to help!
The error occurs because the PC is not yet enrolled in Extended Security Updates. In this case, I recommend enrolling the device in ESU first. Kindly follow the steps provided in the link below:
https://www.microsoft.com/en-ca/windows/extended-security-updates
Once done enrolling, restart the PC and try to update the device again.
Bernard: I thought the purpose of KB5126256 was, in so many words, to facilitate ESU enrollment. Catch 22?
In any case, I hadn't planned to enroll. Am I stuck with seeing this error recur every day, with no (other) way of stopping it?
KB5126256 is an update preparing the PC for ESU. Moreover, since you do not have a plan to enroll, try temporarily hiding the update by following the steps in the link below:
https://www.elevenforum.com/t/show-or-hide-updates-in-windows-11.22868/
Note: This is a non-Microsoft website. The page appears to be providing accurate, safe information. Watch out for ads on the site that may advertise products frequently classified as a PUP (Potentially Unwanted Products). Thoroughly research any product advertised on the site before you decide to download and install it.
