You disabled reserved storage months ago. Then the big feature update landed, and Storage settings calmly shows the reserve again — enabled, full size, as if you never touched it. Windows is not mocking you. This is expected behaviour with a simple cause, and the fix is the same twenty seconds as before.
A feature update is not a patch. Under the hood it runs a setup process much like a fresh Windows installation — and fresh installations ship with reserved storage enabled. The state you carefully set belonged to the old installation; the new one starts from the default. Monthly quality updates never do this, which is why the change always seems to arrive with the big yearly update and catches people by surprise. The correct response is boring: verify, optionally switch it off again, and build the recheck into your post-update routine.
👆 Enabled again after the update — the default state of a new installation, applied by setup. Your files and apps were not touched.
Feature update setup migrates your apps, files and settings into what is effectively a new Windows installation, then swaps it into place. Reserved storage is part of the installation defaults, controlled by the setup process rather than carried over as a personal preference.
That is also why there is no supported switch that makes your choice permanent across feature updates. Anyone selling a permanent block is selling a servicing problem.
Do not trust the feeling that the drive shrank — feature updates also leave a large Windows.old folder behind, which is a separate and bigger pile. Measure both.
DISM /Online /Get-ReservedStorageState and read the state lineTiming matters. Let the update fully finish — including the follow-up restarts and the first update check — before changing the state, so you never fight the in-use error.
DISM /Online /Set-ReservedStorageState /State:Disabled in an admin windowSince the state can reset once a year, treat the check like checking tyre pressure after a long trip — a scheduled glance, not a repair.
Twenty seconds, once or twice a year. That is the entire long-term cost of keeping the space.
The video walks through the state check and the disable — the same two steps you will repeat after each feature update.
▶️ Watch Full VideoNo. Monthly quality updates leave the state alone. It is feature updates — the large version upgrades — whose setup can apply the enabled default again.
Usually Windows.old, the previous installation kept for rollback, is bigger — often well over 10 GB. Remove it through Temporary files cleanup once you are sure the new version is stable.
Only in the indirect sense: if the drive is nearly full, setup may not find the working space it needs. Keep 15 to 20 GB free before a feature update, or re-enable the reserve for that week.