Windows Update fails with “Something went wrong – Undoing changes” unless installed via ISO

Hi everyone,

I'm facing a strange issue with Windows Update on my laptop and I wanted to know if anyone else experienced something similar.

Problem:

When I install updates through Windows Update, the update downloads normally and during restart it goes up to 100%, but then I get the message:

Something went wrong. Undoing changes.

After that, Windows rolls back the update.

Observation:

Interestingly, updates that start directly from the “You're there” stage sometimes install correctly.

Policy change I made:

Previously Windows would automatically download and install updates and frequently ask for restarts. Because of that behavior, I changed the policy to manual download and install so updates would not start installing automatically.

Thermal precaution I tried:

Since my laptop has a faulty CPU fan, I also limited the maximum CPU state to 99% in Power Options to prevent aggressive turbo boosting and reduce potential thermal throttling during the update process.

Another important observation:

If I install the same update using a Windows ISO (in-place upgrade / repair install), the update installs successfully and does not fail at 100%.

Possible hardware issue:

My laptop currently has:

A broken battery

A faulty CPU fan

So I'm wondering if the update process might be failing due to power or thermal issues during the installation phase.

System info:

OS: Windows 11 Pro Insider Preview

Channel: Release Preview

Current build: 26200.7840

Update that fails: KB5077241 (Build 26200.7922)

Questions:

Can hardware issues like a damaged battery or faulty CPU fan cause Windows Update installation failures?

Why would updates succeed when installing from an ISO but fail through Windows Update?

Which logs should I check to identify the exact cause? (CBS.log, WindowsUpdate.log, etc.)

Any suggestions, troubleshooting steps, or similar experiences would be appreciated.

Thanks!