Windows Shutdown as Seen from Your App — Surviving Exit Notifications, Restarts, and Power Loss Correctly (archived 2026-08-30)

Abstract

A Windows Update overnight restart corrupted measurement data — that kind of accident can be prevented by design. This article covers, from primary sources, how to receive exit notifications such as WM_QUERYENDSESSION and PRESHUTDOWN, how to finish cleanup in a few seconds, and how to save so that a power loss does not leave a broken file. Archived version of https://comcomponent.com/en/blog/windows-shutdown-handling-for-apps/, as published on 2026-08-30. The live article is maintained and may change after this date. First published 2026-08-21.